Recording projects transactions with own bank accounts and books

Hi
Need some help?

We have a project that brings its revenue through a separate bank account within our accounts in QF (a physical accounts also exists too).

Any revenue that is generated for it through other banks are invoiced to us by the project; we then forward that amount to the physical bank B, by tagging it through a purchase invoice for the main company, we also then tag it to that project

As regards to income for the main company, the payments received through PayPal and other sources are tagged and invoiced to our clients as general sales (4000), the money we forward to the project through bank transaction how do I account for it?

If the project tags invoices sent to us as an additional sale, that would increase our turnover

Is there a best practice for recoding money coming back and forth for these types of transactions, and how would I account for it in the year end accounts, making sure it doesn’t affect my turnover