If you have plugins you aren’t using, or have gotten rid of or replaced, it’s always a good idea to go through and straight up delete them.
You can always re-download if you discover you need one in the future.
Why? Because it’s less code you have to maintain through updates, and it helps you avoid potential vulnerabilities that lie in those files just existing on your servers.
Caveat: If you are contemplating getting rid of a plugin with custom or detailed settings, see if you can do a backup of those settings or customizations before nuking it from orbit.