Of the two master models shown the Flottentorpedoboot 1941A is possibly the better known.
Motorkreuzer is more obscure. This concept essentially emerged as a one of the alternative studies eventually lead to M-class cruiser (Leichten Kreuzer 1938) in the abortive Z Plan. Design had an all-Diesel propulsion plant compared to other designs.
Following are projected views for Motorkreuzer as per 1938:
Comparison of designs according to Whitley 'German Cruisers of WWII' (in German):
Hope this adds to understanding the origins of the kits.