The developers of MacFreelance don't have the game listed on their website which could also mean that the product is not discontinued from development.
The only place I've found it was on a third party website, but even so, no download was available.
Because of that, it's impossible to say if it works on OSX Sierra or not. If you have the setup package and Sierra OSX, then simply try to install it.
Additionally, contact the developers of the application using the following link: http://www.macwareinc.com/macware-about-us.html
