I'd say no since none of the other past sequel characters have returned.

I can always hope that her and Daria will be in A&O5. (And Princess, too.)

i highly doubt it, cause - like sentinel said - none of the characters in the sequels came back. sure, it might surprise us and make a big change to the franchise cause sure it's pretty obvious Daria's coming back (since she's a part of the pack now), but for now i really doubt it

Didn't Princess have a one-second cameo with King in A&O3? (This scene: link) (Just because there are no differences at all, I doubt these are just character remodels like the one in A&O4 that look like King.)

Claudette, Stinky, and Runt have come back (twice) so what's to say that Daria (and possibly Princess and Lois) won't be the same for now on? I just thought of that. In A&O4, she was just as important as they were in 2 and 3.

Characters that I see returning eventually: Princess, Daria, Fleet, King, and maybe Magril and Lois (To be honest, I'm surprised we didn't see at least a minor appearance of Fleet and Magril in A&O4 like we did with Lilly.)

@LillyOmega Runt, Stinky and Claudette have to come back in each film because they're Kate and Humphrey's kids.
Also, I now really doubt that was King and Princess in A&O 3 because why would they watch the games when King has hate towards the Western pack. I would think he hates the Northern Pack as well since Nars seemed fine with the agreement that Alphas and Omegas could mate.

@SentinelPrime89: Wasn't exactly the case with Balto and Jenna's pups in Balto's sequels. Only two of them are important (unlike all of Kate and Humphrey's pups in A&O). Aleu only appears in the second, Kodi only appears in the third.

Edit: For some odd reason, I feel like they're showing favoritism to them by only bring them back and none of the other sequel characters now that I said that. I like the pups, but that realization just hit me.

And good point. But it still looks too much like them not to be, honestly. To me, at least. The one in A&O4 that looked like King had noticeable differences, where as the one in that scene has no differences from King that I can notice.