And that’s really the problem: this only works if Blizzard is willing to portray the Alliance as anything other than “perpetually morally-superior.”
That being said there is something to
I feel like the most plausible thing that could happen with this is that AU Yrel shows up while we’re off in the Shadowlands and the following scenario occurs:
Yrel: We followed the Mag’har orcs here to Azeroth. They’re evil and destroyed Draenor!
Turalyon: I knew it! The orcs allied with the Legion once, they must’ve done so again! The Light is never wrong!
Meanwhile, over on the Horde side…
Eitrigg: Please don’t trust them! I saw first-hand that Yrel and the Army of the Light were enslaving innocent orcs!
Turalyon: No orc is innocent! Besides, why should we believe anything you say after Teldrassil?
Horde as a whole: We’re screwed, aren’t we?
Not to mention that the “Light Mother” is more than likely an Alternate Xe’ra, who could have plausibly sensed her own destruction at Illidan’s hand, and now wants not only revenge on, say, Velen for letting it happen, but also wants to reclaim Turalyon as her puppet.
It would at least allow the Alliance as a whole to be cast in the role of “misled faction,” where only a select few individuals (Turalyon, Yrel) are the “bad actors” who are truly irredeemable.