Hi skynetcom ,
Unfortunately, there is no way to do what you want with Multi Inventory.
You'd need to make the transfers manually. If you want to keep transfers history, you could use Inventory Logs.
You also can update the inventories values automatically using ATUM Export Pro but don't sure if this would fit your needs.
Of course, if you think that this is a must-do for Multi Inventory, open a suggestion here, and if enough users demand it, we will consider adding it in future versions.
Regarding the question about if we can develop this add-on, I'm sorry, all our team is busy improving ATUM and its add-ons and developing new add-ons and the app. We don't provide this service. If you need the feature, you should hire a good developer to help you. We'll be happy to add any needed hook (after studying it ) and to give some hints to the developer.