Of course, you're right. I got the wrong one. I meant something like this:
https://usb.brando.com/usb-3-1-front-panel-header-type-e-to-usb-3-0-20-pin-header-male-extension-adapter-for-motherboard_p21792c0042d015.html
Dan-cases.com says "available in November" on the homepage and "The A4-SFXv4.1 will be available on Caseking, OverclockersUK, SFFLab and Dirac - Japan in November/December 2019." if you click on "buy".
V4.1 is listed on Caseking (silver only, right now).
Changelog on dan-cases.com:
Looks like I'm going to have to wait for an AM4 ITX board with a Key-A (/Type E) header.