If you are converting the licence (validation is a different thing) to have an EASA CPL/IR issued based on your experience, you will need to do the theoretical course and the exams, as pointed out by others. Doing ATPL theory is the most convenient way, as it covers CPL/IR/HP/ATPL.
If you want to get a multi-pilot type rating issued (airline, bizjet, private - it makes zero difference), you will need to have passed all ATPL exams before the start of the course, ref FCL.720.A(b)(3).
No shortcuts in Europe, I'm afraid.