X10 SBUS input gives steady flickering

[XPS]

"- I cannot use the Taranis and XPS-J1 transmitter module in a setup that requires an SBUS output out of a Nano or RFU "

Correct - it works, but frames are dropped, so it should not be used. This is the fault of the Taranis itself as it doesn't output the correct frame rate for the SBUS protocol.