It seems the Qnap QSW-1208-8C switch doesn’t work well with mixed 10GBE and 1GBE connections.
Specs:
PC 1
Asus ROG Maximus XII Formula
i9-10900K @ 5.1GHz
onboard AQtion 10GBE
onboard Intel 1GBE
Intel X550-T1 10GBE
Optane 905P SSD
PC 2
Gigabyte GA-H270N-WiFi
i3-7100T @ 3.4GHz
onboard Intel 1GBE
Qnap QXG-10G1T 10GBE
Intel X550-T1 10GBE
Windows 10
