Do y'all think if I ally in the Ghur Battlemage from Cities of Sigmar that my opponents will buck over giving him the +1 to casting rolls the warscroll says he gets for the battle taking place in her home realm? It seems totally legit to me. The General's Handbook: Pitched Battles 2021 couldn't be clearer that we're to use the Realm Rules on pages 12-13 and that's as Ghurish as all get-out.
There wasn't, no. It seems like it would be in General's Handbook 2021 if it was going to be anyplace, and I'm not finding it where I would expect to find it (under Realm Rules on page 12). Realms of Battle don't receive any attention in the Core Rules at all that I remember. Maybe they've just gone away.