I dont think it will be at all easy for you to get the megane ecu running in the clio, as in im not even sure if its really possible to do without having access to turn off the immobilisation etc.
The megane engine wont bolt upto the clio gearbox.
Easiest way to do it would be fit the pistons from that engine into your engine with a set of new rings, and then bolt on the turbo and manifold, and then run it on aftermarket.
Or use your existing bottom end with a 197 head to get the compression right and then just use the turbo and manifold.
If you want to use the complete engine and box then you'll need to get new shafts made etc too, so it becomes slightly less trivial to do.