Waka 1 Skip

Explanation

In Agata, the first Waka fight can be skipped with no consequences. The trigger permanently disappears if Ammy leaves Agata by going to Tsuta or Taka, so it doesn't interfere with later trips.

With KT's

The trigger for the fight is too large to just jump around, but it can be avoided by KT'ing up to the ledge above the guardian sapling cave entrance.

Demonstration: https://youtu.be/xQJmnMdIIww?t=713

With Brush Adventure

In NG, a Brush Adventure can be performed directly from the room with the Guardian Sapling to the cursed patch in the hollow tree near the Mermaid Spring. This warps Ammy past the Waka fight trigger, skipping the fight.

Demonstration and timing: https://youtu.be/GiPfnF-QXow