However I'm not completely sure if it's possible with my H8000fw, closest match I found in the modules was the fir filter/convolution fir module. How should I approach this program, which modules should I use?
We haven't tried morphing on the modular platform at Eventide…yet.
Real morphing implies the transformation of an algorithm into another, rather than a cross-fading between the two. It implies a LOT of math and control math modules and very likely audio modules that can change their structure. There is no precise answer to your question at the moment, other than a significative amount of work attempting to create a morph. I would start from something very simple rather than from a complex thing like the one your link points to.