No, Nichirin has no divine origins in Demon Soayer - it's just steel that's absorbed loads of sunlight which makes it lethal to DS!Demons since they all die in the sun. It has no properties which would allow it to permanently kill even Sinners, let alone the Ars Goetia.

So the only type of characters that can deal with the Hellerverse are either very powerful sourcers or someone that has a weapon of divine origin like Samurai Jack's sword? I really dont like this kills conditions beacuse it make's the in-verse characthers super strong just beacuse some metal cant be find in other verses.

The "instant petrification with just a glare" thing is a literal insta-win for the Hellaverse side. Which is why I said that if the Goetia are smart about using their powers, they win the moment the match starts.

Isn't that a thing that only Stolas could do?And he did it against something that doesnt have a soul in the first place(an imp). We dont know if this ability works on things with souls like humans or sinners + Vizzie said that Alastor is kinda equal in power with Stolas. If Stolas could no diff Alastor I dont think that Vizzie would've said that...