If Frieren is transported into the KnY world and fights a bunch of local demons, then she’d likely conclude they’re the same shit as in her own world. Then I bet she’d kill Nezuko first and then ask questions.
However, if it’s Nezuko and Tanjiro being transported into the SnF world, I think Nezuko might stand a chance. Frieren would likely notice Nezuko isn’t the same sort of demon as she typically fights, get a bit more on the defensive side, and in the meantime Tanjiro can intervene and explain stuff.
I think it depends a lot.
If Frieren is transported into the KnY world and fights a bunch of local demons, then she’d likely conclude they’re the same shit as in her own world. Then I bet she’d kill Nezuko first and then ask questions.
However, if it’s Nezuko and Tanjiro being transported into the SnF world, I think Nezuko might stand a chance. Frieren would likely notice Nezuko isn’t the same sort of demon as she typically fights, get a bit more on the defensive side, and in the meantime Tanjiro can intervene and explain stuff.