....... and the synthesized voice is a bit of a challenge for me to listen to--but I understand why some people would want to use it.
WRT the sound, I think Musescore can send MIDI out to your device, so you can get better sound. (I use another software for this so don't know too much about Musescore MIDI out. But, I do know that you can input notes via MIDI in with Musescore.)
You can export Musescore to MIDI. It uses MIDI to play back the score within the App. You can also export to MP3 and flac audio as well as various graphic formats.