I tested MP3splt for the purpose of splitting up a large FLAC file into a number of single FLAC files this week. Please be aware that the batch process fails to generate a single FLAC file for the last documented track in the CUE file. Use the program with caution as you're about to experience data loss if you decide to keep the splitted files and delete the original unsplitted FLAC file after exiting the program.
According to Github a similar bug report has been created in November 2019 (https://github.com/mp3splt/mp3splt/issues/351) but I'm unable to find a newer version which fixes the problem. MP3splt latest update dates back to 2014 (http://mp3splt.sourceforge.net/mp3splt_page/home.php).