I don't remember which of the Ezio trilogy was my favourite (I enjoyed 'em all, even the Constantinople one, which I think some folks didn't like)...but I've grown to really like AC Odyssey.
In terms of overall enjoyment, I think I can say that AC Odyssey is my favourite.
(I haven't played all AC games, tho': stopped after AC4BF, and only got back w/ Odyssey)
Odyssey's just pretty, and the setting was one I really liked, and the characters were pretty good. It wasn't perfect (some of the writing/pacing was off, esp. for the 1st DLC, the microtransactions and the chase for 'orichalcum' isn't great, a lot of missed opportunities and underutilized locations particularly in the 2nd DLC, etc.), but, even after 600 hours (finished NG+, and am now doing just 'weeklies' for orichalcum lol), it's still fun to dive in, even if it's just once or twice a week, now.
Kinda wish Kassandra were AC Valhalla's protagonist, tho'. That or more stories/content for Odyssey (e.g., Alexander's conquests)