It's so peculiar to hear this kind of metal sung in your language. I've never heard heavy and power metal in a language that is not english... Except for Nanowar of Steel that sometimes sing in Italian, but they are a big exception and they are a parodistic metal band.
In Italy it seems like musicians are ashamed of singing in Italian when they play rock and metal stuff. Maybe because the audience doesn't appreciate in the first place, so bands think it's just useless trying to sing in Italian and then being labeled as "cringe".

I do know Heroes del Silencio though. It's the only Spanish-speaking band I know 😅