Mercuriall Audio "Euphoria".

Will the "old" plugins be ported to the new 1.5 modeling technology?

Let me answer from a different angle.
With Euphoria release, our intent is to have one platform to host all our products. So that there is only one plugin to update and improve.
We intend to move all existing products under one roof. Which means, the code will be updated or re-written.

At this point I do not have information if each existing plugin will be updated to NHY 1.5 (Neural Hybrid Engine). It will require more analysis to understand how deeply the existing code will need to be changed (or entirely re-written).

We will share the news with the music community as soon as we have specifics.