In and out

Instead of the transition directive, an element can have an in or an out directive, or both together. Import fade alongside fly…

import { fade, fly } from 'svelte/transition';

…then replace the transition directive with separate in and out directives:

<p in:fly="{{ y: 200, duration: 2000 }}" out:fade>
    Flies in, fades out
</p>

In this case, the transitions are not reversed.