The word can have swearing but not genderisation which might be offensive (mother) nor allusions to sexual dominance (motherfucker). Nor, other possibly offensive connotations. It seems that the word is commonplace and people won’t stop using it, so an alternative to the word may be useful. But the problem with alternatives, is that people might not use them unless they carry a meaning that’s attention grabbing in some way, and when it comes to this word it needs to be able to be used in either a serious (non-funny) or comedic way.
Mother/father is inclusive and a drop-in replacement at least syllable-wise.
I say “muffuletta”, which is a type of sandwich.
Problematic with the use of meat & cheese in the traditional recipe
“Motherfather” could accidentally be interpreted as a transphobic insult, possibly.