I never thought there was any credence to this stuff about them only having the rights to specific factions. They actually mention the Beastmen a few times in the first game, don’t they? In fact, they mention quite a few other factions.
I can’t really buy it, tbh, without seeing some kind of official statement that they don’t have the rights to other factions. I remember them saying the thing about not going outside the licensing, but I’m pretty sure they meant like “don’t add in World of Warcraft or Lord of the Rings” into the game.
In fact, as I recall they talked once internally about Beastmen, but just worried that they’d seem too similar to Skaven since they’re both animalistic humanoid factions. Which I can get, but I still think that besides maps and weapons, a new enemy faction of Beastmen is probably the most likely thing we can expect to see in terms of game content we directly interact with (ie, not cosmetic). New playable characters seem less likely, but I still reeeeally hope they will add some new ones eventually (especially a Lizardman, like my idea of Eztli the Skink).