MacOs to iOS sync works for me. However, the bookmarks on the iOS devices do not exactly have the same folder structure as on macOS: on iOS my bookmark bar bookmarks are interleaved with my Other Bookmarks. Not a big issue but something to be resolved.
So I had added a MacMini and an iPad to my sync chain. Today I added an iPhone by going to the MacMini and creating the barcode and scanning on the iPhone. The device was added, but the screen on the MacMini was stuck in the, “waiting for device” screen.