“The Unhappy Girl”’s effect only applies to “manual” changes. You can still change the monster’s position with an effect.
If “The Unhappy Girl” is in attack position and her controller uses “Waboku” or “Kuriboh” to take no damage from the attack, the attacking monster still cannot change battle position.
If “Tyrant Dragon” or “Hayabusa Knight” attacks “The Unhappy Girl” in attack position, they cannot attack again that turn.
If “The Unhappy Girl” is flipped face-down and then flipped face-up again, then her effect is reset and any monsters that battled with her before can change their battle position and attack again.
If “The Unhappy Girl” applies her effect to a monster, and “Skill Drain” is then activated and resolves, and “Skill Drain” is then destroyed afterwards, then “The Unhappy Girl”’s effect is re-applied and the monster that battled with her before “Skill Drain” was activated cannot attack or change battle position once again.
If your opponent attacks your “The Unhappy Girl” and you use “Magic Cylinder” to negate the attack, then “The Unhappy Girl”’s effect is not applied.
If you take control of your opponent’s “The Unhappy Girl”, her effect on your monsters from previous attacks is still applied.