It’d be tricky to do but technically you could link to those V1 pages directly from V2; however, they’d be different pages themselves. So any modifications to one would have to be replicated on the other.
I heard a V1 to V2 conversions is in the pipeline so you could finalize everything in V1, then transition all pages to V2 while building in this linkable action into the V2 page. The problem with this approach is that they’d be displayed in an entirely new page devoid of the SFDC header and footer.
As far as I know there’s nothing in the pipeline to toggle between a V1 and V2 version of the same page. You can’t on click go from a V2 to V1 page (as far as I’ve tested) but you can click on a link from a V2 page, include Id parameters, and go to the “page preview” of that record in V1.
