Px4 for a new flyer as sbus convertor?

I’m busy getting started with fixed wing and I bought a ft tiny trainer a taranis qx7 and an xsr receiver.

The issue I appear to be getting ready to run into once my freight forwarder delivers is I didn’t realize when ordering during my lunch break is the xsr is sbus only no issue for quads but for fixed wing is an issue

So I was wondering instead of ordering a sbus to ppm convertor to connect to the servos/esc can I use the px4 as a sbus convertor with th main autopilot features disabled for now.

See I need to keep costs down, but I do know eventually I also want a Fc for RTH/WP/Loiter etc. but for now I just want to learn to fly so if I can use the px4 as a basic convertor and enable AP features as time goes on it would save me from ordering more or replacement hardware.

But as I’m new to this I’m not sure if It will work or if it’s just going to be a headache.