Thanks for the clarification and explanation, @pazos.
I will take a look when I getting time for it.
KOReader is always evolving and becomes new functionality

so I'm more likely prefering new releases without doing the work of changing it manually every time.
Maybe someday will be the possibility to select and change the font for the Alt status bar and Status bar directly in the KOReader menu
Thanks to jberd for giving me the right way and Frenzie for answering.