Paul Spring said:I'm thinking some place more temperate where there was less danger of getting nasty tropical fevers. Perhaps a colony in OTL Uruguay or northern Argentina? Chile, perhaps? Was there anything in these places that would attract German investment or German settlers? On the other hand, maybe somewhere north of the Spanish colonies - like somewhere along the shores of OTL Chesapeake Bay? Perhaps the Germans could come hoping to find more gold or wealthy native civilizations to loot, but end up discovering tobacco instead. It could be something like Jamestown except 60 years earlier. That would certainly mean a very different future for North America.
Another possibility - the Protestant Reformation is even more successful in the German principalities, so the Spanish offer assistance to German Catholic refugees in setting up their own colony where they can live as good Catholics under Spanish protection far away from the heretics.