>>44130936HGSS technically has little post game since for some reason people now aren't couting Kanto as post game... but HGSS is still up there. Pokeathelon is actually pretty dang fun, and shitmons are actually really good in it.
BW2 has quite a lot of content related to battling such as the PWT gaining more options, and then the Black Tower/White Treehollow which is not only a great place to grind XP, it's actually pretty fun as a "randomly generated dungeon" since you can't use items.
Pretty much just take HGSS and BW2 with you. Ignore
>>44130983Most of SwSh's postgame is basically just endlessly grinding Max Raid battles so you can play online, which you obviously won't be able to do. The only worthwhile postgame in SwSh is behind a $30 paywall, where you'll still need to grind Max Raids constantly to get mileage out of it.