This happens every time I fight online, I use a character a lot and then there's always that person who's like "ugh I'll teach this person a lesson by kicking their ass with their own character to show them they know nothing about how to fight"
Me and this one Ryu player from the offline scene had a mirror match....lets just say he got owned.....very badly lol.
I always end up losing in a mirror so i never do it unless im playing with friends I guess i just dont like being kicked and taunted after losing a mirror with a random so i dont bother