hey is it possible to mod an analog delay pedal with an expression pedal input so i can control the time and get those trippy oscillation sounds ?
Yup, I've done it with a Dan Electro tremolo (Tuna Melt I think) to control the speed of the tremolo.
The fact that it's digital makes no odds, the principal is the same.

You'll need a normally closed switching stereo jack, an expression pedal with the correct or close pot value and understanding of the circuit and where the pot control fits into it.