would a witch of heart be able to change someone's classpect?
No.
The game has no mechanic of changing Classpect.
Sincerely
SN Tech Support (Gear)

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would a witch of heart be able to change someone's classpect?
No.
The game has no mechanic of changing Classpect.
Sincerely
SN Tech Support (Gear)
fecipher twitter, 8-4-2020: "Mitama: Poet Witch"
[Card Showcase] Much like her father, Azama of the Hoshidan monks, Mitama seems not to have a care in the world, loving haikus and slumber above all else. Now, she has assumed the mantle of a witch: a class from another land. Clad in robes of pitch black, she commands black magic whilst twirling in mid-air, making sport of oncoming enemies. (Illust. Shizuki)
Card stats/skills:
B20-022HN Mitama: Poet Witch Witch/Cost3(2) White/Female/Tome 50ATK/20SUPP/1-2RNG
"Lava splatters him. / The volcano blows its top. / Still the fool stays put."
Black Magic Haiku [ACT] [ONCE PER TURN] If you have exactly 3 allies, and of those allies, 2 have 50 attack and 1 has 70 attack, your opponent chooses 1 card from their hand, and sends it to the Retreat Area.
Well-Drawn Magic Square [ACT] [ONCE PER TURN] [FLIP 1] Until the end of the turn, this unit gains +20 attack.
Illust. Shizuki
More Fire Emblem Cipher Series 20 translations!
A Witch of Hope could have slightly more abstract powers - after all, a Witch, as far as I can tell, manipulates what’s technically already there, not create, so ‘creating new possibilities with belief’ isn’t something this particular classpect combo should do.
A Witch of Hope could plausibly be able to manipulate Hope to their wims when fully realized, which is a plenty powerful thing on it’s own considering ‘Hope’ itself is an umbrella term for ‘positive emotions, belief, faith, possibility.’ Being able to influence these things in people or situations, whether through the powers themselves directly doing so or using abilities to make it so is a gamble, and I suspect Hopebound players struggle with gambles and uncertain outcomes a lot (which would make Seers of Hope some of the most neurotic people...)
Anyway. Witch of Hope. The inner machinations of my classpect are an enigma.
I’m mildly annoyed at myself for not thinking of this in time to write it into the posts themselves, but...
Thief - Page - Knight - Rogue can be distilled to ‘I can’.
Prince - Heir - Maid - Bard can be distilled to ‘I have’.
Witch - Seer - Mage - Sylph can be distilled to ‘I know’.
fecipher twitter, 17-2-2019: "Celica: Maiden Sacrificed to the Fell God"
[Card Showcase] Alm and Celica walk separate paths of their own choosing across the land of Valentia, each in the other's thoughts all the while. The reunion that awaited them at the end of their long journey, however, was a most horrible one: for Celica had offered her soul to the mad god. Reduced to a mere puppet, she seizes upon Alm, baying for yet another offering! (Illust. Senchat)
Card stats/skills:
B16-???SR(+) Celica: Maiden Sacrificed to the Fell God Witch/Cost5 Red/Female/Sword 70ATK/0SUPP/1RNG
[SR] "Nothing can stop Duma now. I'm sorry, Alm..." [SR+] "I heard a voice. A very... kind voice. It said everything would be all right, and to have faith in Falchion."
"Offer your soul!" [ACT] [TAP, FLIP 3] If your opponent's lord is Leveled Up, send that lord's topmost card to the Retreat Area. (Afterward, your opponent chooses their lord's new topmost card from the cards presently in their lord's stack.)
The Mad God's Blessings [ALWAYS] Your opponent's lord cannot Level Up via the effect of a skill.
Evil-Tainted Brand [ALWAYS] If you have 4 or fewer cards in your hand, this unit gains +10 attack.
Illust. Senchat
More Fire Emblem Cipher Series 16 translations!
fecipher twitter, 16-5-2019: "Shade: Soulless Sorceress"
[Card Showcase] There lives a most fiendish arcanist who abducts maidens and puts them to blood sacrifice. It seems that Shade has become but the latest of that arcanist's sacrifices, and as a result has been transformed into a sinister witch. Stripped of her love for her companions, she is now naught but a puppet, cursed to wander the dark woods on an unending hunt for more prey to sate her master. (Illust. Shidzuki)
Card stats/skills:
B16-065N Shade: Soulless Sorceress Witch/Cost3 Red/Female/Tome 50ATK/0SUPP/1-2RNG
"Hee hee hee... whERE... HAVE You gOne? Die die dIIIEEE... I wiLL kill... ALL of yOU!"
Slaughterous Lesson [ACT] [ONCE PER TURN] [Send all cards in your hand to the Retreat Area] Choose 1 other ally. Until the end of the turn, that ally gains +30 attack.
Outpouring Malice [ACT] [ONCE PER TURN] [FLIP 1] If you have no cards in your hand, draw 2 cards.
Illust. Shidzuki
More Fire Emblem Cipher Series 16 translations!
fecipher twitter, 21-2-2019: "Witch: Sacrifice Fated for Puppetdom" and "Jedah: High Priest of the Duma Faithful"
[Card Showcase] Once a woman's soul has been offered to the god Duma and she has been reborn as a witch, her humanity can never be restored. Though Jedah, high priest of the Duma Faithful, knows this well, he nonetheless sacrifices his followers one by one. His crimes against nature will continue until the day that his grand amibition - the restoration of Duma, the War Father - is fulfilled. (Illust. Kazuhiro Taneda, Setsu)
Card stats/skills:
B16-????? Witch: Sacrifice Fated for Puppetdom Witch/Cost2 Red/Female/Tome 40ATK/0SUPP/1-2RNG
"DEATH... TO THOSE WHO WOULD DEFY LORD DUMA..."
Will-less Tool [SPECIAL] You may deploy this card even if you already have an allied "Witch", and you may have 2 or more allied "Witches" at once. [SPECIAL] You may have 5 or more cards with the same card name as this card in your deck.
Offering to the Darkness [ACT] [Send 1 card from your hand to the Retreat Area] Until the end of the turn, this unit gains +30 attack.
Defiled Magic [TRIGGER] When you deploy this unit, if you have 2 or fewer cards in your hand, draw 1 card.
Illust. Kazuhiro Taneda
B16-????? Jedah: High Priest of the Duma Faithful Cantor/Cost5(4) Red/Male/Tome 60ATK/0SUPP/1-2RNG
"The hour is come for the world of man to return to the gods' control! It is the dawn of an age of fear and chaos, cradled in Duma's shadow!"
Sacrificial Rite [ACT] [ONCE PER TURN] [Send 2 cards from your hand to the Retreat Area] Choose 2 cards whose unit name is "Witch" from your Retreat Area, and deploy them.
Fell Pact [TRIGGER] At the end of your turn, if you have no cards in your hand, draw 2 cards.
Illust. Setsu
More Fire Emblem Cipher Series 16 translations!
Friendsim Volume 1: Ardata Carmia & Diemen Xicali
Guess: Ardata Carmia - Witch of Heart
Ardata is more of a caricature than a character, but what personality she does have is clearly strongly Active-leaning. She forces others to essentially rewrite their words to praise her, and focuses exclusively on how people can benefit her, assigning them no other value. The 'good' ending of her episode also features her extended monologue on the topic of her identity and jealousy toward other people for being someone she isn't. While her livestreaming and internet 'fame' could be a Light cue, and her lusus being a tick could be a strong Blood cue, this monologue sounds much more Heart-influenced than either, and her sign (her identity, even) is obscured. She shares some of her negative traits and her overall situation with Vriska, in fact, which could imply she is a Thief. However, she doesn't seem to have a Thief's usual tendency to convince themselves that everything they do is for the benefit of the people around them, at least to the degree of the canon Thieves in the series. She is perfectly aware that it's all a constructed farce for her benefit. She could very well be a Witch, manipulating the identities and desires of herself and those around her, considering her tick lusus does not actively seem to be a threat to her, and she even uses it as a footstool.
Guess: Diemen Xicali - Mage of Hope
Hope is not strongly signaled as his Aspect, but is also not strongly contraindicated. He makes several references to knowledge, seeing, and looking, which could place him as either a Seer or a Mage. He also seems comparatively more focused on his own wants and needs, though not oblivious to the main character's. His hardships and losses, early in his life, could be an indication of Mage status as well, despite his tendency to keep a somewhat Hope-ish positive outlook on his fate, for the most part.