I have Mitsunari and Kiyomasa, both up for some action.

Kiyomasa's part of the watch so he is available for watch-related duties. He will also be all over rebuilding the city when that time comes because heck yeah, rebuilding fortresses, Kiyomasa lives for that.

Mitsunari is probably willing to help with rescue efforts (he is secretly worried about some people, shh) and his weapon form might be of some use, his sword-form will allow for someone to gain a boost of speed that might be useful during the aftershocks (those who can resonate well with him might even be able to teleport a short distance).