Pretty much what Scott said. The Shaped Sheet has some functionality to aid in going the other way, but I don't think that the OGL sheet has any import or translation features. I would not try copying, vaulting or transmogrifying characters. Too much potential for bad or useless extra data. I'd just re-build from scratch, concentrating on things you know you are going to need immediately to give them priority. Depending on how ambitious you are, you could look at the script for the D&D beyond character importer (check to make sure it's still operational in this current state of format flux). It imports characters into Roll20 from a structured JSON fille. You might be able to write a macro or script that could pull data from a shaped character and spit it out in the right format for import into OGL. I don't know, I've never really looked into it. I suspect the headaches would be so great as to make it easier to manually re-build.