Is there an English word for "awaiting approval"?

I would probably use the word "pending".

But you may find these other synonyms more appropriate.

You don't await for something, you just await it (see green line below).

I don't see anything wrong with awaiting approval in a general sense, though, as suggested above (and in NGrams), pending does seem the most appropriate.

"Pending" is a fantastic choice, but my first thought was "submitted" as in "submitted for approval".

If there is a good chance that any given entity will be considered invalid by the system, I would say that the entity was pending classification, rather than pending approval.