Spoiler:
I am obsessed with mystery games and play pretty much any I find. Here is a bunch...
Aviary Attorney - this has birds in it so I like it. Sort of Ace Attorney ish but with a neat art style. My only complaint is that it's a bit short.
Why Am I Dead At Sea - I enjoyed this, not a long game but enjoyable mystery and interesting mechanics. It's an RPGmaker game if I recall correctly.
Orwell - I guess this counts as a mystery? It's not really the same type of mystery but it fits the genre. You watch people in a dystopian society and that's fun.
Bohemian Killing - Has some flaws, but it's also quite interesting to play. Can't say much more about this one. Worth trying.
Sherlock Holmes: Crimes and Punishments: This is a must play if you like mysteries. Mystery mechanics are great, leaves you a lot of room to solve things on your own. Second to Obra Dinn in terms of mechanics. Also its Sherlock, you can't beat that.
I played some other good mysteries which were like... flash games or mobile games that I would struggle to find now. One game that I've been looking for was like... I think the title was 111? Or something like that. It was an apartment number I think. But that was like my favorite mobile game a long time ago. It was sort of visual novel ish and I think like one of those games where you find items and solve puzzles.
Bookmarking this so I can play every game recommended that I haven't yet
Will post more games if I find them somehow