ROT13 and upside-down text (flip text)
Python 3, 120 bytes

many bytes saved thanks to @JonathanAllan

lambda s,a='abcdefghijklmnopqrstuvwxyz VOďƄɹ5ʇη^MXʎ2ɐʠ&gt;Pəɟ6ɥ!ɾʞ|W ':''.join(a[(a.find(c)+27)%54]for c in s)


Try it online!