I'm not completely sure what you're asking. If you mean 'are they valid phrases', then yes, but they're awkward.
'Granting loans' or 'Granting credit' would be better. Possibly 'the act of granting credit' depending on the context.
If that is what you meant, then your question should be phrased 'Is it acceptable to say "loan granting' or "credit granting" when speaking about a bank's activities?'