If there is that would be wonderful!
It has taken me 20 years to uncover that Dedross (Hoxton 1777) came from Droz (Switzerland - French Speaking 1748).
On my journey, I asked a French person living in London to write down the alternative spellings for the (English) phonetic (Deadrow). Expecting a couple of options, I got two pages of possibles!! Fortunately, my ancestor was literate and there was a written example of his name (from 1777) - but this too was 'anglicized' from Droz to Dross. It also seems that my ancestor added the "De" at the front of his name to imply some level of nobility as in "Of". Many "French" immigrants did this to gain favor with their new hosts.
I'm pretty sure that there is no easy conversion formula, given all the variables. Some people, especially from Eastern Europe, just chose a new name. In a similar vein on a visit to Hong Kong, several years ago, I learnt that Cantonese women, on arrival, would pick a name from a gardening book - depending upon which flower they thought the prettiest!
Nigel