@Joseph-TP Hello Joseph, I managed getting the 3 HDD working also on the BE9300 router by connecting them throug another hub. Attached you will see a screenshot. The only point which is not working...

Hello, I've purchased TP Link BE9300 router. I do have 3 external HDD's. I've connected the 3 HDD's using TP Link UH720 USB 3.0 hub to the router. Unfortunately, I see only one from the three hdd's...