Can I deactivate the Stock Transfers and Inventory Tracking plugin?

Can I deactivate the Stock Transfers and Inventory Tracking plugin?

Yes, you can always deactivate the Stock Transfers and Inventory Tracking plugin from the Purchase Subscription screen. You can approach this screen either for the Plugins screen or from the Manage Account section. If you are coming from the Plugins screen, you need to click on the Deactivate button on the Stock Transfers and Inventory Tracking plugin tile. If you are coming from the Manage Account section, you need to navigate to the Already Active section, on the Purchase Subscription screen, and remove the tick from the activation checkbox on the Stock Transfers and Inventory Tracking plugin tile to mark the plugin as Inactive. However, you can always choose to reactivate the Plugin, during its subscription cycle. 
Plugins in Tagrain are either Subscription Based or License Based. So the price that you pay for your plugins is based on the number of POS terminals that you have in your setup and the number of licences that you have acquired.
There will be no change in your subscription amount in the current billing cycle if you are only deactivating the Stock Transfers and Inventory Tracking plugin AND not updating your Store / POS count.