What, you mean actually realise bass figures into a playable right-hand?
Firstly, Finale has no 'understanding' of figured bass: the symbols are either entered as lyrics or as chord symbols. To get Finale to understand that the characters 5 and 3 in lyrics when styled in a Figured Bass font, means D and B when below a G, but G and E when below a C...
Secondly, constructing a playable part is more of an improvisational art than an algorithm to follow. Most continuo lines are not complete - there are plenty of unspecified chords that must be assumed by context.
This is never going to happen with Finale, unless it suddenly becomes sentient. Dorico has built-in figure bass support, so it knows what notes are in a given chord, but even that is a long way off from auto-realisation.
As usual, Peter has a clever solution that will do what he says it will do.
This does assume that the user can understand figured bass and is not using the routine as a crutch. If one does understand figured bass and uses MIDI keyboard input, another semi-solution that occurred to be would be to copy the bass line onto the upper staff of a keyboard part and then use the repitch tool to replace the copy of the bass line with suitable chords.
Like Ben, I don't expect a useful automated realization routine is likely even if possible.