You can add your own songs for piano as MusicXML files. You can f.ex create MusicXML files yourself with any notation program.
Adding songs is very easy. Here is how to upload them:
Go to Songs tab and press +.
Click on Upload file
Browse for your MusicXML file
Choose the track you want to play
You can play the song and save it or exit without saving.
Name the song, artist and pick a genre for the song.
Press save and that's it; the song will automatically be added under My Repertoire --> My Songs.
Supported MusicXML files: .xml, .mxl (compressed music .xml)
Remember to respect copyrights! Please check the following for more information about Yousician Terms of Service.