Changing spoken voice to sound like someone else?

I’m writing some dialogue and before involving the actors I’d like to record it with myself in both roles so I can rework it in context.

What’s the best way to change the voice of the “other” character?

I found this video:

…linked in this article on stackexchange:

Is this possible with Ardour?

Melodyne is a specialized tool, very few other softwares can do this to the level Melodyne can.

You can do basic pitch shifting etc in Ardour, just like you can in many software, but you will not get quite the same result because of the level of detail Melodyne opens up.