This is an FTP server app built for the Xbox One but compatible with other uwp devices aimed at providing the highest level of access possible. It is based on the FTP Server library on https://github.com/ZhaobangChina/FtpServer
retail: https://www.microsoft.com/en-gb/p/retroarch/9n1hpz6x31d5?rtc=1&activetab=pivot:overviewtab
To make work on retail you must remove the run full trust capability