IIRC talking vertical to horizontal will only be affected if you are more than 5-10 miles from the mobile.
I would suggest getting something like this and rigging it so you can manually rotate it between the two positions.
https://www.amazon.com/Bracket-Pole-Mount-VESA75-100/dp/B00BCRRUQ2
Before I built a full cockpit I clamped a pair of vesa pole mounts to my chair’s arm rests and used Velcro strips to attach my HOTAS. It worked out quite well but your mileage may vary depending on the type of chair and desk you have.
Pole mounts I used: https://www.amazon.com/dp/B00BCRRUQ2/ref=cm_sw_r_sms_awdb_btf_t1_tYfuFbPK49FH0