No. "FOR UPDATE NOWAIT" is not implemented in OQL.
FOR UPDATE NOWAIT is a specific command to Oracle databases.
On the contrary, OQL is rather a database agnostic dialect, in which you cannot specify an Oracle dependent syntax like that.
What you could do is to add that specific parts inside a java action. You can directly use SQL string via JDBC in java actions. However, If you insist on using OQL, you can pass it to java action and then get its SQL string via built it method so that you can append for “for update no wait clause” and execute it via JDBC.