>>53922861Sword and Shield unironically. People were very harsh on it due to it being the first game where they publicly announced the dexcut even though LGPE did it a year beforehand and other games kept doing it, plus they mishandled the rationale as to why they did it (they could have just said that they don't find it necessary to add in all of the Pokemon and at least it would have been an honest answer).
Sword and Shield still had 400 Pokemon catchable between the two of them in the main game and over 200 more added in DLC that you don't even need to pay for to technically get. I would recommend doing Wonder Trades during your playthrough to see if you get anything interesting not in the standard Galar dex. In addition to mere catching, this game introduced marks so you have a lot of incentive to catch the same species over and over again if you want a specific one.
If you get the DLC, there's actually a ton of stuff to do. You can farm for resources in the various DLC areas, do two other battle facilities which are pretty unique, and of course battle people. These games were made to battle people in with the amount of QoL to training. You can probably pick it up pretty cheaply too if you typically buy your games from other people. I have no idea how the expansion pass version of the game works but I would think it's all just loaded onto the cart and not a separate one time download.