The world is full of joke phobias, and bad Greek renderings of joke phobias at that. There is a special place in hell for the mangling of Greek that is Coulrophobia.
If there’s a real phobia associated, it’d be symmetriphobia, fear of matching things in general (though I’m not clear from googling as to whether that is a real phobia).
I can make up a word for the phobia if you’d like. harmostos for “matching”. The Ancient Greeks didn’t wear modern socks, and the Modern word for sock is a borrowing from Italian; but LSJ tells me that podeion was a sock or legging. So harmostopodeiophobia.