We just wrote about a 3.5" Ryzen Embedded SBC a few days ago, namely SECO SBC-C90 single board computer, after mentioning there were few such AMD options in the 3.5-inch form factor with the only other board we covered so far being IBase IB918.
But there's now at least a third option with Kontron introducing SBC-VR1000 3.5-inch board powered by AMD Ryzen Embedded V1000-series or R1000-series processor, and designed for "intensive edge computing and graphics applications" including digital signage, digital casino gaming, kiosk, retail, banking, education, medical imaging, as well as industrial control and automation.
Kontron SBC-VR1000