。
She looks very elegant.
Literal
She [topic-は] very elegant appears.
見える here means 'to appear, look like.' Pairing it with the adverbial 優雅に gives the pattern ADJ + に見える, the standard way to say 'looks ADJ.' Not to be confused with the related ~ように見える, which compares against an explicit standard ('looks like X is the case'). 優雅 carries a literary, refined flavor — closer to English 'elegant, graceful' than the more everyday きれい.