Combining two themes functions!

Hi guys

I’m considering to buy another theme (business directory) because of the functionality it has. I have the X theme currently running at my site http://www.strengthsbank.com. I want to keep the X theme because of some functions (mainly shortcodes, which is a plugin exclusive to X theme), but also want to use PP directory theme alongside because it’s intended for that and more powerful. I know I can install WP in a subdirectory and use PP directory theme inside, but I also want to use some functions of the X theme.

When users are in the subdirectory where the directory theme is installed, there will new menu items for the directory. How would you show the menu of the main theme on the subdirectory but preserve the menu items on the directory.

One more thing is the homepage. What if I want the directory theme to show my homepage elements and among that are the recent blog posts, which are posted in the X theme.

I don’t know if achieving that is possible but it’s like combining two themes together and get the functionality of both.

Thanks