LGF, you can't.

The Variant(s) and Main reflect each other in the number and names of pages and the method of presentation is identical across each.

The best you can achieve is to set the design to (vertical) scrolling.
Remove all the unwanted content from the Variant. Do not delete any page.
Add in your new variant page by page.
Where you want to skip a page, just empty that page and shrink its height right down. The smallest it goes is 48px.

Switching from Main to Variant would therefore always hit very close to the right place.
You just need to fill the 48px with something that matches the site dynamic.

Acorn