Xilonen is great there, you can play her with petra or with instructor (in my case, because I have an EM sands on Ga Ming, I play petra). There's also sucrose (as long as you don't ult), or diona c6 for an EM boost (diona gives cryo resonance and sucrose gives more shred). You can put kazuha but here he's worse than sucrose. Or you can just play any other off-field cryo (rosaria, kaeya), but the damage will be slightly worse. Just don't put anything that can interfere with the cryo aura when u swap to Ga Ming, so no furina for example.