。
She's full of goodwill.
Literal
She [topic-は] goodwill [with-に] is-filled.
善意 (ぜんい) means 'goodwill' or 'good intentions,' and 満ちる (みちる) means 'to be full of' or 'to be brimming with.' The に marks what something is filled with. ~に満ちている is a literary expression — more elevated than simpler alternatives like 善意がある ('has goodwill'). It suggests she is overflowing with good intentions, not just possessing them.