Using MSI, You can set your stock warehouse/channel from a different region. Using MSI, You can't able to hide products of supplier. You can just set different stock for a different warehouse.
In MSI, Your product doesn't hide or don't show any cheapest price product. Your concept seems to vendor management.
You can check more details from here,
https://devdocs.magento.com/guides/v2.3/inventory/