I think nearly all professional tax preparation programs that do imports will import Desktop TT. I don't know about TT Online, though. It's nice of you to consider their computer system tools for your return(s). Also, Intuit has "Intuit Link" for some of what you ask. And you don't always need to be the go between. The financial institutions are providing download/import for the professional preparer, similar to DIY TT.

It really seems like you want to drive this manually. Are you sure you don't simply want to consult with someone, but keep doing your own taxes?

Have you asked some revered friends who they are using? Make appointments to interview new CPA or financial planning consultants now, of course.