This might be a stupid question and to me its allready so clear but i want to make sure that is this a mistake on the book or something….

On every other game Inquiry has been fel based skill and on BC at the table found from p93 it says that its Int based:

After this again in skill section it says that its fel based skill and again it character sheet…

So this is a probably a mistake ? To me Inquiry is totally based on ability to intecract with people.

one friend of mine keeps telling me that its int based skill and i need we need to clarify this. There was no mention in errata or faq.

Have you had conversations about this ?

It can be either depending on how the player approaches his Inquiry. There's an entire sidebar in the skill section (p92) concentrating on using different stats for the skills.

Fel Inquiry would be asking around for facts, going up and talking to people. Int Inquiry would be doing research through cogitators and coalescing disparate bits of information to come up with the result. Both are quite valid.

You can even make an argument for a Strength Inquiry roll, walking around Intimidating people till they tell you what you want to know.

To me it would seem that going around chatting with others to get information (the default descriptor) could be a use of Charm while the threatening version is a use of Intimidate (which is Willpower-based in BC). The research approach is most likely Intelligence-based.