Yes, we’ve done this. Works surprisingly well. You may want to put a range on some battle board abilities - say 24” from the warlord so that you don’t get abilities attacking enemies at the other end of the table.
The game flows well, we played with all players on a side having their own battle board, and with similar but not necessarily the same forces. All players on one side took their turn together. All went well, felt like a battle , everyone was involved, looked good.