Spain by far.
1: Survival of the fittest. Franco’s Spain survived the war while Hitler’s Germany was wiped out. This proves that Germany was weaker.
2: Germany wanted Gibraltar to push Britain off the continent but chose not to invade Spain as they did Yugoslavia and Greece to remove Britain. So clear sign that the Germans were afraid.
3: Hitler didn’t like Franco and even thought the Republican forces might be useful, but did nothing. More proof that they feared Spain’s military prowess.
4: Germany wanted a half a continent of living space and failed to acquire it. Spain already one and half continents of living space before and has a half a billion Spanish speakers running around while German is now just a regional language.
5: Spain was a Super Power the sun never set on, Germany failed to get its special place under the sun.
6: Spain got away with the Inquisition while the Holocaust backfired on Germany.
7: Franco got his Monarch while Hitler did not get his living space.
8: Nazi Germany never developed Super Weapons. Franco’s Spain eventually 1970s weapons that Germany could have won WWII with but didn’t.
I’m sure there is more proof, but obviously Spain is far stronger.