Synthweaving is extremely profitable at higher level. I have made about one and a half milion profit just from crafting the force-master critical master crafts (artifact with augment slot). Also, if you are raiding then operation bosses will drop schematics which produce bind on equip gear similar to raiding level, which again is pure profit.
Synthweaving is pretty crappy to level characters with, but in the end its very profitable, if you do it right.
A master craft costs me 0 credits (No missions, I gather the materials) and brings me back 150k credits per craft. Is that good? Its amazing. Synthweaving is a great profession if you are a raider. You can craft and sell gear on the auction house which has the same stats as hardmode operation gear. But to get the schematics you would have to raid of course, since they are bind on pickup. The cvrafted gear however, is not.
here is a link to one of the many, many designs:
The crafts can also crit an augment slot, making them better than the vendor token tier gear. The first critical craft is already reserved for 400k credits.