Plenty of singletrack marked on those maps (and colour graded as well. I have ridden Ischgl-Scuol-Livigno and plenty od trails around Davos and you will be spoilt for choice.
A word of warning – if it's marked black then it will probably only be rideable in the downhill direction.
If you can understand some Italian then this site has 90+ tours in the region.
This site could also be useful