Go see the guys in Mountain Spirit in Samoëns they run a shuttle up to Joux Plane. I think it was a tenner per shuttle but from up there you can drop down other side to Les Gets or back to Samoëns with plenty of natural ‘off piste’ trails. Its not a bike park, trails are occasionally marked but mostly if you head down you will end up back from down in the valley. Difficulty is Red(ish).
The telecabine from Samoëns gets you to a few well marked blue red and black trails. As above – it is not Morzine etc don’t expect berms or well maintained trails.
If you like steeeep then between Samoëns 1500 and Morillon 1100 there is an ‘unofficial’ trail called Chicken Run. It’s to the skiers left of the new piste down to the new lift. I believe some of that trail was used on Enduro World Series.
Alternatively get a Guide (Thomas at Mountain Spirit) and an e-bike and the whole area is your oyster.