The common way to deal with this in games is to have two copies. One player node with ScriptA and a copy with ScriptB.
Now When Mode 1 is selected the player object with ScriptA is enabled.
Mode 2 is selected then the player copy with ScriptB is active.
This is actually very common in games, for example a character shown in the inventory is a copy of the one in game, without all the walking code and that attached.