My oldest grandchildren are 12 and 13. I have considered directly asking them how they feel. On the face of things, there is no issue. The younger one just thinks I'm 'weird grandpa'. The youngest is too young to care.
Parents thereof, well, my children are all fine. Their spouses, uncomfortable but deal with it. Their opinion doesn't mean much to me, as long as they aren't destructive to my relationship with the grandchildren.
Names, they call me what they always do. It's up to them if they feel the need to address me differently, I'll never ask them to do so.