Pro Tools only supports a Max I/O of 32 in and 32 out so you can only use one interface at a time.
Regarding Studio One or any other DAW, that depends on what system you're on and how experimental you want to go to make it work.
If you're on a Mac you can set up an Aggregate Audio device (although we do not support that configuration with those two devices), it may work, it might not. Read this article:
https://support.apple.com/en-us/HT202000. Go to the user forums (
http://forums.presonus.com) for community assistance if you need help.
If you're on a PC, no, you have to use one device, the ASIO driver for the Studio 192 does not host any other ASIO device (even if made by PreSonus). you'll need to use one device.