I have two story ideas and am posting their blurbs for now. If I come up with more ideas featuring swapped bottoms, I'll add them here. If I collect four or five, I might start writing one.
It'll probably be a groveling pursuit after losing the love of his life, plus a swapped bottom.
First idea:
A genius jungler retires due to injury and breaks up with his former mid-lane twin star. He becomes a coach and support player, then gets together with his fanboy ADC.
Second idea:
A cheerful, silly little lucky charm gets abandoned by the Crown Prince and is taken in by his childhood friend, the top scorer. Includes some plot involving the Crown Prince having a child.
Third idea:
The top discovers that he's just one of several fragments of the original top. After splitting up with the original bottom, he gets together with one of his own fragmented selves. (Narcissistic romance)
Theme: Be brave and pursue love.