Add a premade nadir logo in 1 minute with Photo Editor ❨Macgyver❩, logo premade with Theta Converter Pro and Photo Editor ❨Macgyver❩ in 4 minutes

(This preparation is good only if your logo size and position won't change, e.g. Never care about big thumb or tripod, or your logo is big)

PREARATION
(1)  ❨Photo Editor❩ create a 2:1 black image e.g. 5388 x 2688
❨2❩   Paste your logo in the middle and save it
❨3❩   ❨Theta Converter Pro❩ rotate the saved image 90 degree down
(4)   ❨Photo Editor❩  open the down 90 degree image> Effect> Color Replace RBG, set color to opacity 0% color code #00000000, touch the black area to make it transparant
❨5❩   Save to PNG, (save to JPG will loss the transparancy)
Done.

Add logo to any 360 photo
(1)  ❲Photo Editor❳ Open a photo
(2)   Paste the transparent logo
(3)   Save 100% retain metadata JPG
Done