I'm not sure if I'm ever gonna include them in any way if I ever get around to my AU!Links meet AU, but I wanted to do my take on the CDi duo! (Wall of text with my thought process under the cut)
I haven't played those games myself, but I did watch playthroughs of the remastered versions of Wand of Gamelon and Faces of Evil. And as hilariously cursed those games are (in gameplay, animations, plot, as well as dialogues), the thing that bothers me the most about those games is that if we look at only the plot, the stories had the potential to be really good. And they just. Botched it. (I have also started to look at a playthrough of Zelda's Adventure, since I kinda want this Zelda to be the Heroine of Tolemac too because it would be fun if she could light-heartedly tease Link for having saved him more often than him saving her, but I don't yet know how to incorporate those details. Edit: Yeah Gami has saved Tolemac too, but I'm not sure if she'll be able to tease Kori about it bc I think I'll also include the cartoon plot for them and I don't remember if either of them is kidnapped in that series but of well. I'm pretty sure cartoon Link gets turned into a frog creature at some point so Kori's dark world form will be since kind of frog.)
Anyway, this is how I would tweak Zelda and Link if I was put in charge to remake those games today with as little as possible change of the things that are there already.
Personality-wise, rather than Link trying to flirt with Zelda every time he gets the chance, they're besties and Link's flirting is actually an in-joke between them where Link is mocking all the nobles trying to woo her. He is not romantically inclined at all (aroace af to put it frankly) and gets really flustered and awkward when people are flirting with him or touchy when it's somebody he doesn't know well. The reason he was imprisoned in the mirror by that Noble Lady Alma in WoG was because he wouldn't kiss her. And rather than just brushing it off like in canon (which is just really weird and a missed opportunity imo), Zelda's "oh nothing happened" was to sooth a groggy and injured Link while the Lady Alma was escorted to a holding cell. So he has some scars from the mirror breaking and his memories of being trapped are mostly somewhat hazy but there. The scars-from-the-mirror idea was shamelessly stolen from the Koridai from @linked-maze (highly recommend y'all check it out, it's currently on hiatus but it's really good ❤), though my version's scar looks more like broken glass then glass cuts, because I want him to match (and share some trauma) with the Shadow Link (aka Flint) from my AU Four Wild Ones. Other than that he's still a hungry goof-ball who is always up for eating like a like-like and bombing dodongos.
Zelda on the other hand is as helpful to commoners and sassy to enemies as hinted in her cutscenes, and whichever of her many suitors she will eventually select one of her (not vocalized) requirement (other than being kind and competent) is that the suitor must not only be okay with Link being a third wheel, they must actually enjoy it and preferably partake in the shenanigans she and Link will cause. This is also why Ganon had her placed under a sleeping spell when he kidnapped her in FoE: The first thing she did when he took her to Koridai was to cause trouble at his fort and nearly escape.
When it comes to their designs, I wanted them to have some similarities in the silhouette, and also stand out a bit from my normal go-to options, but still contain something from the CDi designs. In Link's case, his canon design is pretty much the same as in the other early canon games, but I felt that poofy sleeves and collar would suit him. I might even make the sleeves even poofier in the future. I did plan on making his hair brown, and might change it to that later tbh, because it was more brown in some of his cutscenes, but I settled on a darker blond for now that can look blond or brown depending on the light. It's also kind of a mullet cut, though his cap normally hides that detail.
And as I wanted Zelda's silhouette match Link's a bit rather than being so very 90's in style, her vest got turned into a poofy-sleeved bolero-thingy. I also find crop tops to be very uncomfortable and not quite matching my version of her, so I turned that into a short dress with shorts underneath. I also decided that early on while on her first adventure she grew sick of not only things getting stuck in her hair but also monsters trying to grab it, so she found herself a villager who was willing to cut it for her, so she sports an undercut (kinda like Colin in TP I suppose, but less of a bowl cut). As I was colouring her outfit I realized I accidentally made her clothes kinda the same shape as Purah's outfit in TotK, but that's fine, that outfit is ✨amazing✨ anyway imo lol
Not sure where in the LoZ Universe Timeline I think they fit, but among the CDi games my order of them is Faces of Evil -> Wand of Gamelon -> Zelda's Adventure (Edit: I have decided that in Flau these games takes place in the Adult Timeline, quite a long time after Spirit Tracks. I did consider the Fallen TL since Ganon is a beast and the CDi games were following the old classic games, but I felt that TL had so many games/ characters connected to it already. And the other two timelines have about a many games as each other, so I went with the adult one because Gami and Kori both travel to different islands and that fit the vibe more imo.)