。
She seems happy being here.
Literal
She [topic-は] here [at-に] be [and-て] happy-seeming [adverbial-に] looks.
Two seem-words braided together: 幸せそう (the ~そう 'looks like / appears to be' suffix on the na-adjective 幸せ) and 見える ('appear, look'). The ~そうに見える pattern doubles up the inferential meaning — 'gives the impression of seeming happy' — softer and more cautious than just saying 幸せに見える. The ~そう of conjecture differs from the ~そう of hearsay (彼が幸せだそう, 'I hear he's happy'); this is the visual-impression one. The opening ここにいて (て-form of いる) frames the predicate: 'while being here, she looks...' The polite ~ます ending sets the formality.