I managed to fix the issue in Arch Linux by updating the firmware (using a proprietary software in Windows) of the VL805.
My version of the firmware (013600 vs 013704) was older than the new one.

Note that to update the firmware, you need to unninstall the windows driver in the device manager, I've had some issues updating it.

This was the response of VIA tech support when I asked them for Linux issues:

Quote Originally Posted by VIA Support
Hi,

VL805 is working well on Fedora 4.13.9-300. fc27.x86_64 .
And we also test on Fedora 4.13.16-100. fc25.x86_64 .
The function is ok, USB device can be recognized under VL805.
This issue should be possibly related to AMD driver behavior

Test condition in VLI:
CPU = Intel i3-8100
Motherboard : MSI Z370 Gaming M5

You can download the latest firmware update tool for VL805 and check the function.
User guide is stored in the folder.
This tool only support on Windows-based.

https://www.dropbox.com/s/68srdt4gmv...0Tool.zip?dl=0

If there is any question, please contact me.

Thanks.
I Hope my message helps other people, since there aren't any other place I've found that shows the true sollution.