AMD Ryzen on Twitter: "From mini-ITX to Ryzen Threadripper, ASRock has your Ryzen motherboard needs covered. Check out their mobo wall at #Computex. https://t.co/PZ9tUo0WDN" / Twitter
To-scale rendition of what a TR4 mini ITX board might look like that I made in photoshop (Threadripper) : r/Amd
Matx/Mitx motherboards for threadripper? | [H]ard|Forum
There is no Mini-ITX for Threadripper, but there is MicroATX already - HWCooling.net