At its Computex 2023 booth, Minisforum is displaying motherboards that will be featured in high-end mini PCs launching towards the end of 2023. Both the Intel and the AMD models feature a PCIe 4.0 slot for a full-size GPU that can be connected via a riser cable.https://www.notebookcheck.net/Minisforum-teases-mini-PCs-powered-by-AMD-Ryzen-9-7945HX-and-Intel-i9-13900HX-processors.722762.0.html
I'm not sure how much market the external GPU mini-PC has.
Though the UM790 Pro and the successor of the HX99G will probably be Minisforum's greatest hits if they can build enough of them.
I already emailed Minis Forum on a 7945HX model that would be preferred in their standard UM format. Cooling will probably be the issue but I will buy one if they make them.