How to update Content Control Tags with Document Custom Prop

Question

I have a requirement Where there are around 80 Templates which contains Different Text  content but some common Properties which need to be replaced with Document Metadata in sharepoint workflows.

 

The Document Templates are attached to List items when submitting List items.

And these Templates are moved to Document Library through WF and then in these Library need to update content Control tags with Custom Properties of Document. 

 I tried below Strategies.

 Procedure 1:

1. Create a Content Type

2. 2.Create Site Columns

3. Add Site columns to the Content-Type.

4. Add the Content-Type to the Document Library.

5. Place the Content control tags in the Uploading Document.

Result : Not working

 

 

Procedure 2: Separate Library for Separate templates .

 

A workflow to create Document item in Library when a List item is created 

 

Result: This Worked but i dont want these as  can edit the Content in Standard Template before Submitting with List items.

 

 

Procedure 3: Using K2 workflows ,this option is not available in sharepoint online version

 

 Can anyone help me on this please.

 

Thanks in Advance