This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
酻 combines 酉 (wine vessel) with 孚, which may contribute sound. The exact historical development is uncertain, and the character is rare.
With no clear meaning, focus on the shape: a wine vessel 酉 beside 孚. If you must assign a mnemonic, imagine a wine vessel being held by a hand (爪) over a child (子), but this is purely artificial.
For スイ, imagine a wine vessel 酉 being swung (スイ) around by the hand (爪) in the right component: swing -> スイ.