@satanasebooks (in your reply to the tags you added to /post/796572207474212864/):
Yup, Marisa used to have yellow eyes in most of the games, but there are few exceptions.
In Touhou 2 she had red eyes, but she also had red hair. It's mostly visible during the endings, as the dialogue portraits are very small and it's hard to make out details in them.
In Touhou 17 she also had red eyes sometimes, but it was due to being possessed by the beast spirits.
In Touhou 18.5 she only had red/brown eyes in the title screen but had yellow eyes during the dialogues (mostly because for the dialogues she reused her portraits from Touhou 18, see /post/701001316149886976/).
In both Touhou 19 and Touhou 20 her eyes remained red/brown.
I'm not sure if there's any lore implications behind the eye colour change since 100th Black Market, maybe there are but I'm not the right person to ask about lore. It could be also that ZUN just decided to change her design (or forgot she had yellow eyes).
Also I hope I didn't forget any other occurrence where she had a different eye colour than yellow. If so I apologise in advance, so please let me know if there's anything missing.