As of this writing, the GraphQL (v2) API does not allow for setting the order status in the quoteCreate mutation. In comparison, the REST (v1) API does provide a field in the POST payload for setting the order status ID. This means that if using the GraphQL API, an extra call has to be made to update the order status immediately after calling quoteCreate - and with rate-limiting, this dissuades from using the v2 API.
So it would be extremely helpful to provide a way to set the order status ID in the quoteCreate mutation.