Would the constellation Leo have been called ‘Leo’ by ancient Egyptians?...................Seems to me it is a Greek/Roman name from their mythology..................
I do not know the name Egyptians would call the constellation, but the constellations have been identifed for a very long time in human History. Whatever ancient Egyptians called a lion would be the name identifying the constellation.
One other note: the original carving may have been of a FEMALE lion, too!