。
She wants to go abroad.
Literal
She [topic-は] overseas [to-に] is-wanting-to-go.
Japanese is famously cautious about asserting another person's internal states directly. To say 'I want to go,' 行きたい is fine — but for a third party's wish, you typically reach for ~たがる, which roughly means 'shows signs of wanting to / behaves as if wanting to.' That's why 行きたい (first-person) becomes 行きたがる (third-person). Adding ~ている (here as ongoing state) gives 'is wanting to / has been wanting to' — a continuing inclination rather than a one-shot wish. The whole construction is one of the cleanest grammatical illustrations of Japanese's evidentiality bias: you can describe someone else's outward behavior, but their inner state stays hedged.