1. Summary
It would be nice, if would be possible view only changes of textr-cli.
2. Examples in other apps
See eyo description:

User can view in output line and column numbers, where eyo will replace text.
It would be nice, if something similar is implemented.
3. Argumentation
This can be useful, because the user needs a visual check of what the program replaces. User can not be 100 percent sure, that there are no bugs in the all texts of the user or all of textr modules.
4. watch
Yes, I read options:
-w, --watch — Watch changes in source file (works only with input as first argument and output through -o or --out-file flags);
This may be similar to the fact that in this request, but I'm don't understand, how it works. For example, I'm tried:
textr Sasha__Test--TextrWatch.txt -w -t typographic-ellipses -o Sasha__TestFile.txt
textr -w -t typographic-ellipses Sasha__Test--TextrWatch.txt -o Sasha__TestFile.txt
But I can't watch changes. If I do something wrong, please tell me.
Thanks.