@Trizek-WMF - please check the following examples or real arwiki accounts with Arabic native speakers.

tl;dr
Regarding the main question of using on mentor list gender-specific titles of user namespace - e.g. utilisateur/utilisatrice for French. Yes, the links will be correctly resolved to user pages even if utilisatrice would be used for a page that is, in fact, utilisateur.

I tested on betalabs arwiki (there is no cswiki on beta and kowiki does not have extensive grammar support for gender). I checked for the case that described in the task - using مستخدم/مستخدمة ( equivalent to utilisateur/utilisatrice) on a mentor list.

1. there are user pages for two mentors with different genders: مستخدم:ET228 - male and مستخدمة:ET200 female.
2. I assigned such users as mentors (and translated the text into German since German language has full gender support for professional roles and pronouns, of course). All seems to be correctly translated (not sure about 'Your mentor' and 'Active today' though. Here is also specific language norm for using gender form for professional/role titles. For examples, in Russian 'mentor' will not have a gender (btw, it's not typical to user what is used for User in ruwiki, there is another much more common word for user), but in Czech the word 'mentor' will reflect a gender. It's complicated and needs to be checked by native speakers.

3. Checked the messages for Mentorship modules on translation to Arabic. Seems that all messages have gender support.

@Dyolf77_WMF, this is for you! :)

• The examples are correct except for the last ligne on the second image, but I think it was fixed since >>
• I did a deep review for gender translations last Friday, checked the results this morning (Monday) on betalabs arwiki and they look correct. Waiting for next train to see the results on arwiki .

@Dyolf77_WMF -- if this looks good to you (now that the train is arriving), you can resolve the task.

Thanks, everything is working fine.