Re-Plumping Dried Insects
"Soft bodied" can come from a number of conditions, but generally, soft bodied insects are kept in ethanol. Adult insects should not need any kind of treatment before being pinned. Nymphs and immature insects should be in ethanol, and I suspect this is what you have. However, they can be freeze dried for a nice effect. One technique that works for females that are full of fatty eggs (such as Orthoptera) is to make an incision on the ventral side with an exacto-knife, and scrape out the contents of the abdomen. Then stuff with cotton, and close the incision. I think you likely have immatures, which should be in ethanol, but this technique would work if you are careful.