There are online converters for it all, the process is a little annoying but works fine and you can do it locally too with various tools: https://www.epubconve

There are online converters for it all, the process is a little annoying but works fine and you can do it locally too with various tools: https://www.epubconverter.com/epub-to-mobi-converter/ https://www.epubconverter.com/epub-to-mobi-converter/