How is better\faster update a workflow on all project sites?

Hello ,

I develop a workflow for SharePoint\Project Server 2016 using SharePoint Designer 2013.

I have a project site template with a change requests list.  The list uses a site collection list content type 'Change Request Content Type'. Each column is a site column.

A workflow 2013 is associated with the content type. I didn't find a way how to create a reusable workflow that can be used by all sites and as the result each site has a workflow. 

Now I need to update the workflow on all project sites. 

Question is how is the better to update change request workflow on project sites? Or perhaps I had to use another approach for implementing the workflow.

Really appreciate for your help and advice.

Best regards,

Slava Shamak