Man-on-Man-Splaining 

When you've run out of women to mansplain to, so you resort to men instead.

"Did you happen to attend last night's amateur radio club meeting?" "Yes, a lot of man-on-man-splaining."

Man-on-Man-Splaining by addat November 13, 2023

Man-on-mansplaining 

the explanation of something by a man, to another man who they perceive as their inferior, in a manner regarded as condescending or patronizing.

There was a lot of man-on-mansplaining in the office today between Bert and Matt.

Man-on-mansplaining by Fz9g3z September 10, 2019