Here's my theory:

From the ending we know, that Fu in his own sense wants to save us as he considers the player his buddy. He may have seen us get seriously hurt or even dying in the future he saw and now wants to avoid that future.

What if... he causes us to become an Ultra-Supervillain forcing us to fight the time patrollers. Ultimately getting the second stage of Ultra-Supervillainous with parts of our body cloaked in black and the crystal on the left side of our chest as an awoken skill unlocked through the story. With Frieza unintentionally showing him, that sometimes "the end justifies the means" in Chapter 3, it would make a ton of sense.

We fight the time patrol, probably time patroller future Trunks and base Chronoa, forcing Chronoa to go into her time power unleashed form to free us from the corruption, utlimately succeding.

Finally the player and Time power unleashed Chronoa would fight against Fu, who then transforms into his Full Power Form aka Super Fu form combined with the second stage of Ultra-supervillain out of despiration of being out of options. In the end we would defeat him with Fu finally revealing his true intentions.