As someone with ADHD Pokemon fan games have been my thing, especially side loading them to my phone.
Pokemon Infinite Fusions has by far been the stand out, filled with endless "ooh, but what about this?!" Moments. It's a new, fun twist on the classic Kanto story, and even features Johto as an absolutely massive post game. It's the only one I have to play on my PC though.
Pokemon XenoVerse is great as well, unique designs, a compelling story and a surprisingly well balanced new type. This one works very well on phones except for Pokemon centers becoming T H E V O I D.
Pokemon insurgence has been the latest to join my collection. It's far and away the most maturely themed Pokemon game I've played (though I've heard uranium is more mature) I'm not finished yet so I can't comment on quality. In lieu of fakemon they opted to instead create a massive number of Delta species, a take on regional variants which have all been interesting at the very least. It's the one that runs best natively on my phone, with only the occasional glitched text