Silas Merlin has retopologised the AV2 male reference avatar, so that it is no longer necessary to decimate the mesh. Decimation with AV1 avatar was less of a concern, but with AV2 due of the increased triangle count, it is necessary to decimate a lot more heavily across the main body. and this process is harmful to the topolgy.
Silas's mesh is exactly 40k triangles and includes repainted textures from the AV1 release. Thank you immensely for doing this Silas!
Silas's file works perfectly with Blender 2.79, but there are issues with using this with Blender 2.80+.
My contribution is just a little different; it will work more easily in Blender 2.80+, materials / textures are embedded, and it aligns with the Sansar Official Guidelines for avatar import / export in Blender (links available at time of posting):
With permission, I took Silas's mesh, and replaced the armature from the AV2 male reference, being sure to re-orientate the armature and retain all of the weights. So what we have here is a texture embedded FBX, created in Blender 2.80, which has the Primary Bone Axis on X, and the Secondary Bone Axis on Y, and can be imported as is into Blender 2.80+ or directly into Sansar (without Experimental Transforms enabled).
The file size is quite large at around 31MB due to the embedded textures. It should work 'out-of-the-box', but you may need to set PATHS to ABSOLUTE, and UNPACK the textures as well.
Additionally, 'User Transforms' have been cleared and exported into the FBX, so it should not be necessary to fix the hand any more.
I hope this helps other people out.