they just look like you put textures on a block which probably is what you did but it looks awful, I would probably add individual leaves near the edges (just a couple) so it look less kinda flat (I just dunno how to explain what looks off) also if you’re gonna stylize the leaves, maybe add a stylized tree trunk texture too (and change the colors so it looks more easy on my eyes)
I am definitely not a pro modeler, but I think those trees look really good! Some of the branches look a little funky though…but if you made a park with these, that would be cool!
I think that in a game, this could work if you’re going for a cartoony kind of style, and for me personally, this does work. But I doubt that this kind of design would work for everyone.