Unless Vince still holds a grudge against Impact as descendent of TNA, I think he’ll just book Mickie as any other WWE legend in for a shot, for better and worse. I think bringing her in and acknowledging her as an Impact champion, “world” champion even, indicates they look at Impact in 2022 as just another larger scale indie, i.e. a fly.
They’ve acknowledged the Viking Raiders as former ROH tag champions on commentary before, and Pearce as former NWA champion (in the lead up to “wrestling” Roman).
I know those are acknowledgments of talents’ past, as opposed to something current, but this is just a one-shot appearance, and she’ll more or less job to a WWE star in the end. Also, when WWE wants to use someone under contract somewhere else, they give something in return and the title name drop is most likely part of the package.