Blackmagicdesign has added VR tools starting with Fusion 9 and DaVinci Resolve 15, which make it simple to work on 360 video projects.
In the first part of the tutorial, I will introduce the tools before going a little bit crazy by trying to convert a 2d photo into a low-res 360 video.
The PanoMap converts between different VR formats like the default LatLong format and different boxed formats.
With the LatLong Patcher you can view a rectangular unwrapped area of the image in the 2D viewer. You can make edits on that section, for example, paint out stitching boundaries with the Paint node.
Afterwards, the LatLong Patcher can transform the area back to the 360 format and you can merge your changes over the original footage.
If you are working in the 3D environment in Fusion, you can film your scene with the Spherical Camera just like you would do with a normal camera in Fusion. Your Render3D node can then directly render out the 360 video. Finally, the Spherical Stabilizer (Studio version only) can help you stabilize shaky 360 footage.
This tutorial uses external resources, that you can find here: