Personally i’d say XY and gen 6 in general, mega evolutions are excellent and they made an actual effort putting lore into the games (plus i’m french so i may be biased because kalos), ORAS were imo the best remakes ever and are exactly what a remake should aim to be.
OG gen 2 or 3 are tied for first, but if I had to pick one, it’d be 3. The remakes were decent but felt off.
3 is probably my favorite, too, and the one I played the most as a kid. I stopped paying attention to Pokemon for a while and missed when the remakes came out. I played them a few months ago and really loved all the content they added. I went in blind and was blown away.