All evc does is mask cpu instructions that the lowest level can't use, which is what allows vmotion to happen. IF the nodes are on a different cluster, that shouldn't matter, its just networking at that point. I can't remember but when we had vcha setup we had it on different clusters, but I don't remember if we have evc on, but again it shouldn't matter. If the active goes down and the passtive comes up they aren't moving they are just stopping and restarting. Outside of that they are replicating the database, which is also just networking.
With everything, test it out and make sure it works, but I see no reason for evc even to effect this.
