mf and dtt/chikai weren't all that great OR fitting for KH3, so I personally don't care if she's gone for KH saga 2.8 final remix prologue. It's time for something new
While I agree that the English versions of all the themes tend to not fit in terms of lyricism (a point which tends to frustrate me considering how great the Japanese lyrics are) I am curious why you believe Chikai in particular doesn't fit KH3.
Totally understand Don't Think Twice (an entire verse of lyrics was cut out for heaven's sake) but Chikai is great imo. Thematically it focuses on the emotions of tiny, particular moments of closeness with someone you care about, being exactly in that moment, and appreciating the person right next to you and wishing for those moments to continue forever. It's about a promise to be together, forever and fully understanding what that means and the emotions behind it. Considering that one of the main quotes that keeps popping up between Sora and Kairi was "I'll always be with you" that seems to fit quite perfectly. There was also the aspect of "even if there isn't a lot of time, try to make the moments you have together count" that Sora was trying to do in the ending. (Let's also not forget that the final line in the song is literally talking about sitting shoulder-to-shoulder watching a sunrise together).
The lyrics of Don't Think Twice kind of drop that nuance entirely and go for a different vibe of "oh thank goodness we are committed now!" which I like a lot less and feels far less connected to the series.
In regards to Face my Fears there are fewer lyrics to speak of since most of it is synth stuff but the lyrics in Japanese again feel a bit less...I dunno cliche-ish? The English uses a lot of more cliche stuff like "I got nothing to lose, how about you walk a mile in my shoes" kinda thing but the Japanese lyrics are about forging a new path, even if you have to start at the beginning and being excited to meet the new you at the end of the road. Uses quite a lot of "map" imagery in its metaphors as well. I also found it particularly poetic with her choosing to use lyrics like (in translation) "the ocean...is not far off" considering how the ocean/Destiny Islands is often used as a goal to reach in the series. (But also, literally ocean = Kairi if we want to go that far).
Also just the closing line: 私の知らない私に早く会いたい (I can't wait to meet the me I don't know) feels almost like a subtle nod towards Sora wanting to help out the other sides of "himself" aka Roxas/Xion (and in part, Ven). Far more beautiful imo than the simple "watch me cry all my tears" in English.
But yeah, just my opinion that the Japanese versions at least have always fit very nicely.
That being said I'm personally still miffed the most about Passion vs Sanctuary. Passion's lyrics are an absolutely beautiful take on nostalgia and things changing as we grow up but Sanctuary always came across as a bit of a shallow generic love song. Hikari also is the far superior song between that and Simple and Clean even just from the title of the song itself, not to mention just the pure symbolism in the lyrics in regards to the game theme. (Though I will say the music video of her just cleaning dishes in her kitchen in relation to 'simple and clean' is straight up amazing).
I love Utada to bits, I really do, but I have always felt like her English lyrics are far less poetic and tend to miss the mark compared to her Japanese ones. I'm not sure if that's because she feels like English-speaking audiences like having the same words repeated back over and over more often or something but she tends to kind of pare her words down and loop them far more frequently in the translated versions which is sad because lots of meaning is left on the cutting room floor.
I hope she continues making songs in the series because her voice is beautiful and I love the themes and lyrics of her music in Japanese, but at the same time it would be nice to have both versions actually feel comparable in meaning. I feel like people who only know the English versions of the songs are missing out on quite a lot.
I do think it would be nice to possibly see other artists featured, though, as that potentially may open up more western interest in more Japanese artists?