Neither franchise follows an overall plot; Final Fantasy is a new world every time (unless it's explicitly a sequel ie X-2, XIII-2 etc.). Zelda mostly takes place within the same 'world' but almost each game is standalone and wholly separate from the other entities with only vague connective tissue between a few titles. Ever since the 'timeline' became a thing 20 years ago, they've tried to explain it and it all comes off very shoehorn-y but I eat it up.
Although Zelda is more connected than FF in that the basic premise stems from the eternal curse in which the Hero, the Princess, and the Evil King are reborn throughout the centuries and millennia.
I kind of like how each game is its own thing for the most part. This makes me want to get into Final Fantasy but I don't know where to start...but then again it probably doesn't matter where I start. I also like the weird Final Fantasy world. It's unlike every other RPG I've played. I haven't played many (or any) JRPGs though. Perhaps that weirdness of the game world is a staple in JRPGs.
I've been looking at the remastered versions of Final Fantasy X & X2-2. Is this considered a good FF game?
JRPGs are definitely a different beast in regards to the world designs. Much more 'out there' and in a different way than western RPGs.
Final Fantasy is weird in that pretty much every game is a different animal with a different magic/skill system and loads of other stuff, but there are a few constants: Gil (currency), airships, a dude named Cid who is an airship expert, and spells like Fira, Thundara, Blizzaga, Cura etc.
X is a fantastic FF game, but it's so much different from what came before. 1-9 are "traditional" FFs - developed by the 'old guard', most of whom split the company between 7 and 9 but mostly after 9 if I recall correctly. So it shares elements with older FFs, but does so much new stuff to reinvent the series and try telling the story in new, cinematic ways. I was playing the remaster until I got a PS4 over the holidays last year, and I was really enjoying the enhanced models and textures and reliving the story and that awesome battle system. Plus, the Sphere Grid system is (imo) the best level-up system Final Fantasy has ever had. X-2 is a different animal... I'm not a fan, but it has its audience. It's certainly no X, though. Picking up both, remastered, for a decent price is well worth it though. On the Switch, it only cost me 25 USD.
Oh and there's a character in X who is so ridiculously designed that he looks more like a Kingdom Hearts character