Transfer Vertex Order | Blender Add-on  

Demonstration
The problem of different vertex order in blendshapes can be caused for many reasons. For e.g. the topology is same but one of the meshes was edited)

I remember the times when I needed to add extra loops to head with the already created blendshapes. And to not break the vertex order I needed to do all operations in exactly the same sequence for each blendshape. It was a nightmare :)

How can we fix it?

With this add-on you can simply copy and paste verts, edges, faces ids orders between meshes with the same topologies in two clicks in pie menu. Demonstration

Optimized and works really fast!

Сopying and pasting takes about 20 seconds on a mesh with 3 million triangles. On a low poly model, it will take a split second.

Blendshape usage

Blendshapes is very powerful tool not only for animation but also for modeling and sculpting (morph target technique). Imagine you have a setuped model in Blender with names, materials, textures, applyed but you want to tweak it in some other software. With blendshapes you haven’t to setup from scratch an imported model with changes. You can just use it as  blendshape applyed to setuped model. And if it turns out that something wrong with vertex order, you can easily fix it using this add-on.

Compatible with: Blender 2.8, 2.81, 2.82, 2.83, 2.9, 2.91

Installation

• Press edit > Preferences > Add-ons > Install > select downloaded file and enable checkbox
• add-on will be available in the 3D view in edit mode (Alt+T to run pie menu)

How to use

1. Select any two neighboring faces on source mesh
2. Open pie menu and click 'Copy Vertex Order'
3. In same order select the same two faces on target mesh
4. Open pie menu and click 'Paste Vertex Order'

Notes

• Ones you clicked copy - the order data will store in memory, so you can do paste operation on other target objects without copy operation each time
• To clear order data - open pie menu and click 'Clear Cache'

bugs fixed