回答

・it's off the subject, but
・as an aside

「說句題外話 」的英語可以用 it's off the subject, but 或 as an aside 來表達。

It's off the subject, but my hobby is watching movies, so I am familiar a little about him.
（說句題外話，我的興趣是觀賞電影，多少了解關於他的事。）
※familiar（熟悉的，親近的，等等）

As an aside, it seems that there will be a new shop in front of the station.
（說句題外話，車站前可能會開家新的店喔。）

有幫助｜0