i do it all the time, well, not all the time but have done it many times. i just moved a superchili into dirt.
so, he is what i did:
i took a 4" peak pot and made long incisions in the pot with sissors and stabbed holes in the bottom of the pot.
next, i put a layer of my mediu(soil) on the bottom of the peat pot.
next, i put the plant into the peat pot and gentlely put soil around the roots until up to the main part of the stem that i want exposed. you may have to trim your roots or use a larger peat pot.
this time, i added some myke mycorrhize to see if that would improve nutrient uptake.
my soil is my own blend of peat(promix), with ground alfalfa, coffee grounds, tea grounds, ground eggshell, kelp meal, rehydrated coir, ground dehydrated banana peels, finings from my shaver. it may have some fine sand it as well.
in the past, i have just taked the basket that sits in my dwc and put that directly into soil and it has worked just fine, rockwool and all. more recently i have started to remove the basket from the roots.
i have also used coir baskets but again, i cut the basket to all the roots to find their way out. i find my pepper roots don't seem to like breaking the walls of coir, tomatoes have no problems pushing right threw - just peppers.
next, i am going to move 2 datil plants into soil, a douglah, a bonda ma jacques and a butchT.
I also go the other way, dirt into hydro. just working on a stalled butchT and a pequin.
good luck.