Restart Player at Transform inside of GameModeBase leaves the character unpossessed when called.
Repro Rate: 4/4
Tested in //UE4/Release-4.27 @ CL#18319896 and the player character successfully respawns, this is a regression.
Results: User is unable to control the player character, with the character frozen in their last animation state and heading.
Expected: Player character successfully respawns and the user is able to control the restarted player character.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-148882 in the post.