If I already have uploaded an iClone avatar via LiveLink to UE4, but then in iClone: 
1) send avatar to CC3 to modify a morph,
2) change a morph amount in CC3, and then
3) send back the now-changed avatar from CC3 back to iClone,

is there an easy way to likewise update only the mesh the avatar in Unreal via the plugin, or would it require
(1) deleting the avatar from UE4, and then (2) going through the whole process of transferring and building the whole new avatar and material set in UE4 all over again?

THX!

Basically, would like to update mesh while keeping the existing assigned UE4 materials.
If I load in new character version it will reset the materials.

Could LiveLink have something added which could update mesh, by name, but not replace its materials.

THX! 

Try adding a morph to the morph animator, and do it in realtime.