External monitor causing system hiccups

I saw past posts about this issue but it's still hitting me on the current MBP 2019.

I'm using external iiama black hawk external display monitor through a Green-Cell USB hub:

https://greencell.global/en/startseite/1954-docking-station-adapter-hub-usb-c-hdmi-green-cell-7-ports-for-macbook-pro-dell-xps-lenovo-x1-carbon-and-others.html

Whenever I connect external display, the computer seems to stop every couple of seconds - the mouse freezes for 0.5s, terminal also - that's very irritating.

Somehow it seems, that I can get rid of this behaviour by changing the connection order of the external monitor but also not always.