I think recalling removes stealth on champions like Akali or Teemo, that need to do nothing to remain stealthed, but perhaps for Evelynn or Twitch, who can move while stealthed, can they recall without removing stealth?
Recalling counts as an action and thus removes "remove on action" stealth effects (which, if im not mistaken, are all stealth effects currently in the game) There is one trick though: If you use a stealth skill and start recalling before the stealth actually kicks in, you will recall invisible (For example with twitch using ambush, then instantly starting to recall and going invisible after pressing b)
actually i will go throught the champs for you:
teemo: he gets out of stealth and cant get into stealth while recalling
eve after rework: dont know seriously
akali: she gets revealed short time (just like when she attacks)
twitch: he will get revealed BUT if you use recall during the 1.5 sec which are needed to go into stealth you will recall in stealth (check twitch re-mastered spotlight, phhreak is explaining)