But back to the op’s topic
; ‘convert multiple patterns of selected track to multiple phrases in 1 instrument’ , impossible mission?
Not at all - as djeroek probably knows, PhraseMate has made this possible for a while. Actually, the idea was prompted by this very thread 
As a proof of concept, I “phrasified” one of the demo-songs:
https://forum.renoise.com/t/new-tool-3-1-phrasemate/44918
My question would be, how the workflow of that tool could be improved?
Because I know that, if it’s not 100% spot-on I tend to not use it at all.