You asked
Best travel lens for the sony a7cr?
For the a7CR, I'd start with the Sony FE 24-105mm f/4 G OSS. It covers wide to short telephoto, and its optical stabilisation helps with dim churches and interiors. If you want something lighter, the Sony FE 28-60mm f/4-5.6 is a small kit zoom that fits easily in a bag. For a longer reach in one lens, the Sony FE 24-240mm f/3.5-6.3 OSS is worth a look, though it's bulkier.
Every travel kit also benefits from one small fast prime for evenings and food. The Sony FE 28mm f/2 is a good companion for that. For the reasoning behind all this, see what matters in a travel camera and what to pack.
Written by Claude from this site's pages.