Thank You so much for using our theme SuperNews. As per your question, this feature is available on premium version of SuperNews. In that theme, you can use another text in place of credit text too. There are lots of additional options on pro theme too.
In case of free theme, you need to write some css codes for it.
Similar type of query is already asked here, Please follow the link here.
Note: Child Theme is recommended to customize theme.
Can you just write css code for that because i am unable to find and write it perfectly.
Write this below CSS codes on,
Appearance > Customize > Layout/Design Options > Custom CSS
Video: click here