Yes, it's possible to create two (or more) diagrams in Visio, save them as web pages, and have hyperlinks in one drawing open pages in another drawing. But it isn't necessarily straightforward. It's pretty easy if all of your links are from one drawing to several others with no return links -- in that case, publish all the docs that are hyperlink targets, then create the links and publish the source document.
But it's more complicated to achieve if you want interlinks among the various drawings, e.g., from to A to B as well as from B to A. The reason is that if you're creating a hyperlink from Visio drawing A to the web-published version of Visio drawing B, the target of the hyperlink doesn't exist until you've published B as a web page. But you can't add the hyperlinks from B to A until you've published A as a web page.
When each document is both the source and target for hyperlinks, it is necessary to use one of two techniques before creating the webpage-to-webpage hyperlinks:
- Publish both maps as web pages, then edit both Visio drawings to add hyperlinks to the published pages. Finally, republish each drawing as a web page.
- Devise strict naming conventions so you can create hyperlinks in advance of saving both TaskMaps as web pages.
If you experiment with doing this you may find you'll have issues with how the linked pages open, specifically whether they display the save-as-webpage navigation panes that appear on the left of Visio-published web pages. If that's the case, let us know as there are ways to resolve that problem.