When I edit lyrics in iTunes and sync the iPad with iTunes, I can not see my changes in Stage Traxx.

iTunes will only update changes to tags (this includes song lyrics) when the automatic syncing of music is enabled. Make sure to connect your iPad via USB to your computer and open the Music screen in iTunes as shown in this picture:

iTunes Filesharing

Activate Sync Music. If you don't want to transfer your whole music library to your iPad, also select Selected playlists,....

2 months later

Another possible reasen you do not lyrics changes from iTunes in Stage Traxx is that you edited lyrics for a song within Stage Traxx. Edited lyrics have always precedence to iTunes lyrics. You can restore the iTunes version, by opening the lyrics editor and pressing Reset lyrics.

Don't use iCloud or Apple Music to transfer music to your iPad. Lyrics will not transfer reliably with these syncing methods.

2 years later
a year later

Got loads of songs in it edited only a few, tried all that you’ve suggested several times. Can see the lyrics in 2 songs out of probably100 but can’t see what’s different about those 2. I’m working Catalina with iPad 5th gen. one strange thing is bottom left of my (music) iTunes page it says syncing even when I’m not. If you press the I next to that a box comes up that says the same message hundreds of times saying it’s updating my iPad.

Ah I see. The problem here is indeed ST3. When you import songs into ST3 through your music library, ST3 will skip songs that already have been imported. I'm not sure if it is better to overwrite existing songs. That would mean that you would loose local edits. And that could happen accidentally for example when you just want to import a new playlist with songs already in ST3.

So my suggestion is to either delete the songs you want to update before reimporting them from the music library or edit lyrics directly within ST3.

10 months later