When using the Battle.net version of Sea of Thieves, while this does utilise your Xbox Live account, please be aware that game invites through the Game Bar are currently not supported.
To invite a fellow player to your session within the Battle.net version of Sea of Thieves, simply go to 'Create a Session' and press the ‘1’ key (X Button on Xbox controllers / Square Button on PlayStation controllers) on your keyboard. A pop-up window will then appear, displaying a list of your Xbox friends, from which you can invite friends to join your session.
If you are already in a session and wish to invite friends, you can do so by accessing the pause menu, selecting the 'Invite Friends' option, and following the same process as described above.
Regarding invitations from other players within the Battle.net version of Sea of Thieves, once an invitation is sent by another player, it will appear as a prompt in-game asking whether you would like to join their session. You can then choose to accept or decline the invitation.
