Hi how could I pull my starters in the second half of pre-season games but not the kickers (P & K) like IRL.
I just played a pre-season game and set in "misc" to pull starters on 2nd half. By doing so my punter were benched and the AI placed a FS in position of punter, result: several blocked punts with recoveries and defensive TDs and bla bla bla....

It should already not pull your Punter or Kicker. My punter stayed in all game successfully after my starters were pulled in the 1st quarter of this preseason game: https://xfl.myfootballnow.com/log/9602.

Did you have a player set in the depth chart behind your punter? Or the person behind your punter was inactive, although I think that scenario would have your punter stay in as P1. Or the FS had somehow found their way into the P depth chart instead of gunner/somewhere else?

Starters do not get pulled if there is no one behind them on the depth chart. The only time this is ignored from what I can tell, is when a player is set to start in two positions according to the depth chart, then they will start in one position while the other position will get filled by the next best player according to your ratings.

Side note, I am not sure what positions get filled with priority over others.

I had the K set as 2nd punter in the depth chart, maybe that's why. I'll try to set only my P alone for the next game and I'll see what happens. Thank you for your answer!

I wasn't sure if you had done that in response to your first preseason game or not so I chose not to comment on it when I was looking. I would imagine that is the issue because as far as I've seen, once your kicker was pulled from being Kicker #1, he would not reenter the game as Punter #2 because he is "benched" from being Kicker #1.

Ok I understand, I didn't think about that but its pure logic! :)

Freaking thank you.
That whole pre-season pull starters stuff is far from ideal - particularly and especially for K/P duty.
EDIT: this option should have a "by position" choice - as does the fatigue settings.
Furthermore, the overrides needs to add quarters. <<<<The actual solution for experienced players. Both would be 100%.