Playshift Requirements in an item's description means that you have to fulfill requirements of this item each time you zone. If you don't, the item simply stops working.

A most common example of this feature is that when you enter any shop while flying a Yalmaha, you won't be flying inside, but the Yalmaha will still be equipped (the condition must be outside is checked and failed).

It is possible that not all of the item's requirements are playshift ones, but in Anarchy's GUI there is no way to find it out - you have to check it in an online database like AUNO or AODB.