Just curious:)

I called my maternal ones Grandma and Grandpa and my paternal was Gran. If my grandfather had been alive, he would have been Grandad.

No LOs yet, but I think they will call my Mom and step-dad Grandma and Grandave (his name) and my dad will be Grandad.

DHs parents likely will be Grandma and Grandpa as well, but DH might push for Oma and Opa.