Legal Question in Family Law in California

Yes. It's called admission pro hac vice. It requires a motion filed by a California attorney on behalf of the client and out of state attorney, however, and the California attorney must remain on the case as co-counsel, though how much work the California attorney actually does after the motion can be very limited. You should bear in mind also that California's Family Law departments in the Superior Courts tend to be rather "clubby" in that the attorneys and judges know each other and there are many unwritten ways of doing things. And that is on top of the fact that Family Law is an area where different states' laws can be very different. It's not like a business contracts commercial code case where the laws are generally standardized. So it could put the party represented by the New York attorney, and the New York attorney themself, at a significant disadvantage.