I had a similar problem and I tried all the recommended fixes to no avail. Track IR worked with XPlane 11 but not with MSFS2020. Everyone kept saying that TIR has to be running before FS2020, which it was. But it occured to me that on my PC, at some point I had to install an Xbox application. I can either start FS202 directly (from pinned toolbar icon) or first start Xbox app and then launch FS2020 within that. Normally I don’t bother with Xbox app. But decided to try. With Track IR already running, then start Xbox app, and then launch FS2020 from XBox app.
That works.