Fritz GUI rated game implementation

[Rowen]

Does anyone know how the fritz GUI handicaps a game when playing a 'rated' game by elo? It seems apparent that if a UCI engine has a limit elo option, such as Stockfish does, then the engine controls the elo implementation, and would then be expressed according to the engines programming.

But some UCI engines and chessbase engines dont have this internal option? and I am presuming that the Fritz GUI implements the 'handicapping' by elo and this is independent of the engine?

If so how does the GUI does this, I am thinking it is either depth and/ or a time handicapping?

The elo range that the GUI presents for a rated game seems to change according to time control for engines that dont have an internal limit elo, but is constant for those that do. Not sure if thats relevant? Any thoughts? Thanks