So are you really about half German half Irish? Like, your dad's parents were both mostly Irish and mom's parents both mostly...
My Mom got into genealogy for a while so I know my heritage pretty well. It is pure Irish on my dad’s side, I think the first generation immigrants were at the great grand- level. Black Irish, for what that’s worth.
My mom’s side you’re right, German predominates but it’s kinda American Mutt. She’s traced it back to three signers of the Declaration of Independence but no Mayflower pilgrims.
I hear a lot of people have family legends of some sort of Amerindian ancestry that get disproven by geneaological research, we were the other way around - no legends but it turned up anyway, which isn’t that odd in a tree that goes back to colonial days. One of my ancestors was a surveyor, commissioned by land speculators to journey out past the pale of settlement and make maps and notes of soil quality and whatever. Anyway, once he went away on a 2-3 year expedition and returned home with a wife that the town church helpfully recorded as “an Indian maiden”. If I knew his route I could maybe make more specific guesses but it’s not a priority.