Several halls, one account
Two venues are two clubs in the same account — separate member lists, separate groups, a single sign-in.
The app in use, recorded.
If you train at two venues, that is two clubs in the same account — separate member lists, separate groups, a single sign-in. The footer says which club you are in, and one tap switches: from then on every page shows the other club’s data.
Who sees what
The account’s admins see every club. Everyone else is assigned per club, so the coach at one hall does not see the roster of the other. The country is set per club too — the fee is shown in the currency you collect it in.