I've not taken a look at Co-Author Plus but it should, in theory, be possible to make WP Biographia see if this other plugin is installed and to work nicely with it.
But ... the changes which are (probably) needed to do this will be deep in the WP Biographia code base which makes the (not unreasonable) assumption that each post and/or page will have one author, which is how WordPress itself works. The impact and effort of doing this would be quite large I'd imagine.
The other multiple author plugins I've seen do work well but it's a challenge to get them to integrate into the WordPress core way of doing things as they subvert one of the core tenets of WordPress, inasmuch as there's always one author per post.
If you having coding skills, feel free to work WP Biographia from GitHub and take a stab at this. If not, then I'll certainly consider looking at this in a future release but not right now.