Yes. As well as installing Valheim Plus on your server (on the Mods tab of the control panel), every player needs to install it in their own game too, in the same version as the server.
The easiest way is with r2modman or the Thunderstore app: install the same Valheim Plus there. You can also find it on Thunderstore: Valheim Plus on Thunderstore.
- Console players (Xbox, PlayStation 5, Switch 2) can't install mods, so they can't join a server with Valheim Plus. For a server with console players, use only mods marked server only on the Mods tab.
- After a Valheim update, Valheim Plus may stop working until a new version comes out. Update it on the server and in every player's game to the same version.
See How can I install Valheim Plus onto my server?
Need help? Open a support ticket and we'll take a look.