If Shadrich and Myranda are able to figure out who Sansa is despite never having seen her in her natural state then I don't see why the Northern Lords would have any problem considering they had known Catelyn for nearly 15 years who even mentions that in Acok that the northern lords often mistook Arya for a stable boy but had no problem recognising who Sansa was. Besides, I feel that both Yohn and Anya Waynood have also figured out her identity.
Ya for SURE I think people really put too much stock in the idea that no one will recognize the Starklings. Wyman is worried about Rickon being a fake bc he was a toddler when they disappeared - that's a lot easier to fake than a 13 year old Sansa! "Oh but Jeyne Poole-" none of those people had seen Arya except Theon and Theon recognized her immediately. Like of course they mistake Arya for a stable boy when she's dressed like a boy and covered in mud! I just think everyone is really dramatic lol, Myranda put the pieces together almost immediately because it's a goofy lie - LF just clearly wants to fuck Sansa, he's radiating it, and sure there are dudes who clearly want to fuck their daughters but this sure is a suspicious time to unveil the daughter you want to fuck who look suspiciously like Catelyn & Lysa, and since Shadrich seems to put it together fast too, I don't htink her disguise is that good.
Also - Yohn doesn't even need to put all the pieces together, he literally knows and has met Sansa not two years ago!! All he needs is to get a good look at her, all she needs is to catch him alone to be like "hey it's me" and he's going to recognize her immediately. All she did is dye her hair like two shades darker and start dressing slightly different, that's not a disguise that's a teenage rebellion lol. She's fine!!
