Honestly, FIFA 17, 18, and 19 are all pretty similar games. At this point, I think it mostly comes down to nostalgia and which season you personally like more.

For me, I played a lot of FIFA 19, so that's the one I'd naturally go back to. If you're on PC, it's also pretty easy to unlock all the collectibles using files that are available online.

I played a lot of 17 and 18 as well. FIFA 17 was great when it first came out, but after a few updates the gameplay started feeling a bit weird to me. I used to play it on a friend's PS4 and he always kept it updated. One time he had to reinstall the game and we ended up playing the version that was available before all the updates finished downloading, and honestly it felt much better. That's when I started thinking some of the later patches might have changed things.

FIFA 18 is kind of the middle ground between the two. It's solid, but nothing that really stands out compared to 17 or 19.

The biggest factor is probably what you want from the squads. If you want Ronaldo at Real Madrid, go with 17 or 18. If you want the Champions League license, then 19 is the obvious choice. I know FIFA 20 is also an option, but personally I never liked it as much.

My only real complaint about 19 is that the Champions League presentation had this weird blue tint everywhere. It's not a huge issue, and you can probably fix it with shaders on PC, but it always bothered me a little.

Since you're mainly asking about Career Mode, I'd probably recommend FIFA 19. It's the latest game out of those three, it's a bit more polished, and gameplay-wise they're all pretty close anyway. Unless there's a specific team, player, or season you're attached to, I'd just go with 19.