I would like to create a workflow that I can copy / associate with other projects

[Anneliese Pretorius]

All the documentation seem to indicate that I have to re-create my workflow for every project, rather than just selecting a saved workflow.

[Mikael Sandberg]

You can create a workflow that is applied to other projects, you do not have to re-create it. You have two options, you can either create a new project using the share settings with existing project:

This will share the settings between the projects, so you have to be careful when making changes since that would affect all projects that are sharing the settings. 

Your other option if you only want to share the workflow between projects would be to create the project and then change the workflow scheme to the shared one. 

Please note that this only applies to company-managed projects, for team-managed projects you would have to recreate the workflow for each new project.