I have server-side app which connect to GA Management API with user credentials after oAuth login. It creates predefined Remarketing Audiences (can be over 30 audiences). I am sending it in batch request because of API requests limits.

Some of audiences are successfully created, but some of them return Quota Error: Rate limit for writes exceeded. Why? It has been sent in ONE request...

Any suggest highly appreciated.

EDIT

I have noticed that when I send batch request with only 4 inserts of audience it successfully pass. I have chunked my batch request to batches of four requests and everything is fine, but it is hack and not satisfying solution... :-/

You are hitting the limits, all the requests you put into one batch request count as an individual request. See the limits and quotas.