Fluently Speaking Baron by Ava Devlin

Harriet “Hattie” French speaks over a dozen languages—but none of them prepared her for this.

Seven years ago, Dowager Baroness Selwyn vanished without a trace. Now she’s been declared dead, and her will is a masterpiece of meddling: Hattie, the first of the seven prodigies the baroness took under her wing during her prime, inherits Starling’s Rest, the manor where they were honed from wayward fledglings into world-renowned talents.

That would be well and fine, but for the baron. The dowager baroness’s taciturn and stormy nephew owns the land the house stands on.
The solution? Marriage. Orchestrated from beyond the grave by a woman who never met a prodigy she couldn’t manipulate.
Elias Selwyn spent years proving he wasn’t useless.

Elias fled Starling’s Rest as soon as he was old enough and hasn’t been back since. He left behind the pudgy, unremarkable child, with only a title to hold up against the sparkling genius of his foster siblings. In the years since, he forged himself into a disciplined cavalry officer, building a life far from the manor full of brilliant wards who made him feel invisible. The last thing he wants is to be dragged back to Brighton and shackled to the girl who once made him feel small—no matter how brilliant, beautiful, or infuriatingly fluent she’s become.