I am looking for expert Solidity Developer who can use current git repositories of existing defi project to create a new one with making some edits
Did you mean someone who can forking the existing code that has already used by most of defi? that's quite difficult to find someone who will able to do that. Visit this site and i hope you can meet what you are looking for
https://forum.ethereum.org/ I guess that will be related to the smartcontract.