Do Nintendo 3DS games work on the Nintendo Switch?
No, the Nintendo Switch does not have any backwards compatibility so it cannot play 3DS games
Does Nintendo 3DS work with Pokemon games Like Pokemon Black and white version or future PKMN games?
No the 3DS game cards are shaped slightly different then the Nintendo Ds. Of course if you could put the 3DS game cards in the Ds lite it would still not work because the features and intense graphics the nintendo 3DS requires for games can't be used on the Ds lite. Don't buy 3DS games for the Ds lite as it just won't work. You can consider buying a 3DS however as the 3DS is…
if you want to play 3ds games on the nintendo 3DS, yeah, you need to buy the 3ds games. if you want to play ds games on the nintendo 3ds, just buy a flashcart instead, there are many flash cards that let you play ds games on the nintendo 3ds, i recommend you buy r4i gold 3ds from r4ids.cn or dstwo card, do not buy other clone cards.
the games might not match your 3DS region. all the 3DS games have region lock, it means that if you have an American 3DS only NTSC=american games will work on that 3DS and PAL=european or NTSC-J=japanese games will not work, same for the European and Japanese 3DS If it is not reading any games, then that points towards the 3DS' card reader being broken, you'll need to have it repaired.