Migrating NPV ISLs

Hello, I currently many NPV 9148's where each is port-channel connected to a core 9513.  Some of those port-channels also trunk.  I have introduced 97xx to fabrics with goal of decommissioning 9513.  For NPV switches, if I construct additional new channels to 9710 from 9148, does this by itself cause an issue?  Put another way can the 9148 establish handshake to both 9710 and 9513?  Second, as I understand it, NPV load-balancing should make any new host flogis anchor to the 9710 until at both port-channels balance.  If I want to stay away from NPV   traffic-map what is recommended way to get host flogis to resolve from 9710?