Take a look at this one from Plugable 7-Port USB 3.0 SuperSpeed Charging Hub with 60W Power Adapter with BC 1.2 for $40. I'd be comfortable and confident installing 4 Moonlander 2 (ML2) spaced apart. Manufacturer said in a review comment, "When the hub is connected to the computer the hub is capable of a maximum of 1.5A under the USB-IF Battery Charging 1.2 standard." So, 5V * 1.5A = 7.5 watts. If ML2 is 1.4 to 1.5 watts per megahash, then 5 megahash is 7 to 7.5 watts.  This HUB can fit 7 USB devices, but we will have to see if ML2 can fit in the provided space and whether excess heat can be controlled adequately.

I know of another 10 port USB HUB and it is 10W per port, but they want $700 for the unit.