CUK ASRock H670M-ITX/ax Mini ITX Motherboard for 12th Gen Intel LGA 1700 CPUs at 125W PL1 with PCIe 5.0 x16 Graphics
Used Mini-itx For Asus Rog Strix X570-i Gaming Motherboard Socket Am4 For Amd X570 Original Desktop Pci-e 4.0 M.2 Mainboard - Motherboards - AliExpress
I hope they finally make Threadripper ITX boards : r/Amd
All the best mini-ITX motherboards for Ryzen, Threadripper, Coffee Lake and Skylake-X - YouTube
ASUS ROG Strix Z790-I Gaming WiFi 6E LGA 1700 (Intel®13th&12th Gen) mini-ITX gaming motherboard (PCIe 5.0,DDR5,10+1 power stages,Thunderbolt 4,2.5 Gb LAN,USB 3.2 Gen 2x2 front panel Type-C) - Newegg.com
To-scale rendition of what a TR4 mini ITX board might look like that I made in photoshop (Threadripper) : r/Amd