Yes. You go to Preferences | Add/Save | Adding books.
Activate "Read metadata only from file name" and change the "Regular expression" that specifies exactly how to interpret the different parts of the filename.
Try this:
(?P<author>[^_]+) - (?P<title>.+)
If you test this, make sure to enter the whole filename as test string, including the file extension. (.lit/.epub etc)
You can also read the filenames as they are, and later swap author/title when you edit metadata for a book. There is a button for that purpose.