Dating USWNT Star Ashlyn Harris

Sophia Bush just filed for divorce from her husband, but she's already dating someone new ... recently divorced U.S. Women's National Team soccer stud Ashlyn Harris.

Sources connected to the pair tell us the "One Tree Hill" actress and Ashlyn are officially a thing. The timing seems sudden, considering Harris only filed divorce docs from her wife and fellow USWNT star Ali Krieger less than a month ago.

Sophia's going through a divorce as well ... in August, she filed docs to end things with her husband Grant Hughes after 13 months of marriage.

Getty

While Sophia and Grant did NOT have kids together ... Ashlyn and Ali adopted a boy and a girl during their 4-year marriage ... so it will be…