I have two 64 bit elf files for one program but with 2 different version. IDA can resolve the function names in one of them while not for the other. I don't have bindiff but I want an automatic solution like this tool if available
You can try and use Diaphora. It is open source, and is probably the best Bindiff alternative out there. That said, be aware that binary diffing might fail in many cases regardless of the tools used.