Yes, I submitted original Robot Master designs for fan contests ever since I was a student, and even after becoming a professional illustrator.
One of the postcards I sent was actually featured in Capcom’s official magazines at the time, as well as in the staff roll of Mega Man 8.
Later on, after I began drawing Mega Man comics, Capcom asked me to design two Robot Masters for the game Mega Man & Bass.
I originally named them “Coil Man” and “Blast Man,” but in the final game, they appeared as “Dynamo Man” and “Burner Man.”