There is yet one other way to deal with segments that don't need translation: just leave them empty.
When you've set CafeTran Espresso 2019 to automatically insert matches in new segments (Preferences > Auto-assembling > Automatic insertion of matches is checked), you can get some content in new segments that you enter.
This content will be selected (the whole segment content is selected). Just press DEL or BACKSPACE to remove the content and navigate to the next segment to handle.
Upon export, CafeTran Espresso 2019 will use the content of the corresponding source segments for those target segments that you kept empty.
Placing of tags in auto-assembled segments, is not one of CafeTran Espresso 2019's fortes.
Instead of tedious replicating the source segment, just press DEL or BACKSPACE and move on to the next segment. You can adjust quotation marks etc. via Find & Replace in the review stage.
This technique is very handy when you have to translate documents that contain a lot of names (brand names, trademarks, other names), that don't need to be translated. Especially, when these names are listed in table cells, like here: