Many modifications
Going from a pattern meant for stretch fabrics to a garment out of non-stretch fabric may be tricky, notwithstanding the alterations for my own body shape.
From stretch to non-stretch
Disclaimer: it won’t work for all patterns!!! Make your own research to check if someone has already done it. I like perusing the Sewing Pattern Reviews or Minerva websites (hashtags #jalie2795 or #softshell).

Jalie already drafted a pattern for softshell, #2679, but I wanted the hood (sounded logical since I wanted a rain jacket).
So I took the 2795 pattern, looked at the size chart, and decided to upsize: from X-Y to Z-AA.
And…I did a muslin from stiff fabric, to check the fit.
First thing I noticed was a big pool of fabric above the butt. That could mean 2 things: either a sway-back adjustment or more room needed around the hips.

I opted to unpick all the side seams for 10 cm and the pool of fabric disappeared. Lesson learnt: more room at the hips so I went with a size BB there.
Wrists were tight so I added 0.5 cm to all of the pattern pieces.
Other modifications for #2795
Those were just for transforming the hoodie into a proper rain jacket.
I didn’t use the cuffs and band. I added some length to both sleeves and bodice to compensate (+11 cm).

Raglan sleeves are always tricky for fit on me because of my narrow square shoulders and tiny upper back. I did some drastic slashing in the pattern pieces! I took 2 cm off the raglan and 1.5 cm on the other pieces forming the armholes.
Instead of sewing the inner collar in softshell, I used some rib-knit. Very comfy and cute with this bubblegum pink color.