The HP USB-C Dock G5 (5TW10AA) is not compatible with Acer notebooks, including the Nitro 5. This dock requires a USB-C port with DisplayPort Alternate Mode (DP Alt Mode) or Thunderbolt functionality, which is not generally available on Acer laptops.

Regarding the ability to power up the laptop in the closed position with the dock's on/off button, this functionality is generally available if the laptop is compatible with the dock and the laptop's USB-C port supports the necessary power and control signals. However, as the Acer Nitro 5 is not compatible, this functionality will not be available for this laptop.