This is a full list of modifiers from status effects in battle. 2.5x evade can be gained from the Third Eye (the menu and description lie), 2x evade is not used in the vanilla game, Attack power up can be gained from the SunShades, and Max Attack Power Up can be gained by the PrismSpecs.
Evasion:
Target has 2.5x evade: 250%
Target has 2x evade: 200%
Target is asleep or stopped: 20%
Target is blind or confused: 50%
Target is slow: 75%
Target is poisoned: 50%
Attack:
Attacker is berserk: 150%
Attacker has Max Attack Power Up: 150%
Attacker has Attack Power Up: 125%
Attacker is poisoned: 80%
Attacker is slow: 80%
Attacker is confused: 25%
Accuracy:
Attacker is blind or confused: 25%
Attacker is poisoned: 75%
These apply to PCs and enemies equally. All of these stack in the order listed, except for berserk, which ignores all the following statuses, 2.5x evade and 2x evade, where 2.5x evade takes priority, and max attack power up and attack power up, where max attack power up takes priority.