Latwy skrypt!

on sneak toggle:

    apply invisibly to the player for 99999 seconds

on sprint toggle:

    remove invisibly from player

    send "Jestes widoczny"

edit:

zapomnialem o uprawnieniu:

on sneak toggle:

    IF player has permission "xd":

         apply invisibly to the player for 99999 seconds

on sprint toggle:

    IF player has permission "xd":

         remove invisibly from player

         send "Jestes widoczny"

(Pomogłem?  Daj like!)