I have a single inverter generator with a floating ground that connects to my house panel using a manual interlock and double breaker. It works well. I have a garage and shop on a separate meter and panel about 20 feet away. Can I add an interlock and generator inlet box to the shop panel and feed both at the same time using a splitter cord on the generator? My main concern is that there are two separate grounds. Could I create a potential between those grounds? Any other hazards?

I have a single inverter generator with a floating ground that connects to my house panel using a manual interlock and double breaker. It works well. I have a garage and shop on a separate meter and panel about 20 feet away. It is a separate feed from the power company transformer. Same transformer that feeds the house. Can I add an interlock and generator inlet box to the shop panel and feed both at the same time using a splitter cord on the generator? My main concern is that there are two separate grounds. Could I create a potential between those grounds? Any other hazards?