Hi Coder8yg
I'm sorry but we don't actually support any 3rd party POS plugin as we plan to have our own POS system.
Usually, the POS plugins are only able to read/write the default WC's stock quantity (that is in sync with our main inventories). But adding the ability to read/write custom inventories is something that the POS plugins should add from their side (or you can find a developer to assist you with this integration).
Best Regards,
Salva.