「Binary Editor BZ」は、実行ファイルや画像ファイルなどあらゆるファイルを16進数で表示・編集できる多機能バイナリエディター。

To open and view the contents of a MacBinary file, you must have a program that is capable of uncompressing the binary file type. You can use Stuffit Expander to open compressed files.

Click Open. If the app that you want to use to open the file type is greyed out, it's because macOS doesn't think there's a valid association between the two.