Leonica is someone who always braves the unkown and will do her best to slay impossible foes. It just won’t be nearly enough to do anything against someone as formidable as Bass. Bass is the strongest being in all media. There is no one who can really challenge him and while her sword skills are powerful, they would not be able to break his barrier. His FTL speed would also ensure that there is no way for her to dodge his attacks for long. Bass wins.