。
She looks cruel to me.
Literal
She [topic-は] me [for-には] cruel-seeming looks.
Three useful patterns layered cleanly. (1) 私には ('to me / from my perspective') uses the composite particle には to set the speaker's viewpoint as the frame. (2) 残酷そうに combines the na-adjective 残酷 ('cruel') with the appearance suffix ~そう ('seeming') and adverbial に — 'in a way that seems cruel.' (3) ~に見える ('appears, looks') is the spontaneous-perception verb 見える, here taking ~そうに as its predicate. The whole sentence carefully marks itself as a personal impression rather than an objective claim — typical of cautious Japanese opinion-giving, where direct judgment about people is often softened.