Question about Sony Playstation 5 Slim Disc Edition

No. It is not possible to play physical ps3 games. It is possible to play ps3 games via paid subscription, in streaming, with no connection to your disc collection. Some accessories are compatible. Check each case individually. Keep your ps3 safe!

The PS5 is designed to be backward compatible with PS4 and PS3 games. Of course some games are not compatible for some reasons, you have to check the games you want.. As for the accessories, I can't really say for certain but there is a big chance they do not support it.