The gaming industry is not ready for that discussion yet, but you absolutely should be able to.

It's being discussed in courts, see e.g. https://www.eurogamer.net/french-court-rules-steam-users-hav....

You should be able to if it is being advertised as “buy”. They should just say gain access to use it or something like that if they are not really selling anything.

If you're in the EU, you can :

https://www.clarionsolicitors.com/articles/reselling-used-so...

It might be difficult in practice though, with platforms like Steam providing no means to actually resell a game to someone else.