I see you have set Q_TAILSIT_INPUT =1, so you control as a plane hovering nose up during hover. Aileron input on TX will roll the plane. If you set 0, the plane will swing nose to yaw direction. Bit 1 will change mixing earth frame to body frame. It will help to fly it better at higher lean angle once tuned. Sometimes document or wiki is hard to understand. It help to refer both descriptions of wiki and complete parameter list.
https://ardupilot.org/plane/docs/guide-tailsitter.html#tailsitter-input
https://ardupilot.org/plane/docs/parameters.html#q-tailsit-input-tailsitter-input-type-bitmask
You should follow tailsitter tuning steps. It is updated recently and clear. Quick Tune LUA applet will help to tune well after you set FF value manually.
Once tuned well, you want to make transition but I guess you may end up spiral due to lack of vertical fin/yaw stability, better to set plane parameter in advance.
There are many tuning points. My Eclipson E VTOL thread may help how newbie learns to tune.