VorpX

vorpX is a paid software that injects into a wide variety of games and either provides a DirectVR mode or a Cinematic/Immersive 3D mode

Available for purchase and download here
It has a built-in SbS display mode that you may want to try first, but if you need support for a different type of 3D display, you can use VRto3D to help with that
Make sure you already have VRto3D setup for your display first
vorpX is 3DVision compatible
Can run in single-display mode using Ctrl + F8 with a gamepad
Can run in multi-display mode with a gamepad or mouse & keyoard
For multi-display mode, it may be necessary to set your primary display to your secondary 2D display, and use Win + Shift + Arrow Keys to move the SteamVR Headset Window to your 3D display

Run the Start vorpX shortcut in the start menu or on the desktop
Once it is started vorpX automatically attaches itself to supported (and many unsupported) games

Right clicking the vorpX tray icon opens a menu where you can select exit vorpX
When you are done playing games with vorpX, be sure to close it, as it will otherwise inject into and mess up configurations of many games

Right clicking the vorpX tray icon opens a menu where you can select Configure vorpX
Per-game configuration is better done in-game though
These settings are recommended for VRto3D (can disable hints)
If you want to use mouse & keyboard, you will want to rebind EdgePeek, Magnifier, VR Hotkey Menu to something other than the default Mouse M so that they don't activate easily

See the above reference for in-game hotkey configuration
vorpX will have various pop-ups that recommend certain in-game settings and whatnot that usually can be dismissed by some on-screen hotkey
Pressing DEL opens the vorpX in-game configuration menu. Most of vorpX's settings can be altered there
The in-game configuration menu can be navigated either by using the cursor keys or by using the mouse. When using the mouse, menu buttons can be pressed with both the left and the right mouse button
If Geometry isn't available in 3D Reconstruction you may want to use something other than vorpX to play the game
Experiment with each game to find what Play Style and what 3D-Strength/Scale looks best
Full VR Mode will probably be best if it's not too zoomed in. Here's recommended settings:
Cinema Mode is probably the next best option, but the screen aspect ratio won't exactly match. Be sure to turn off all the Curve settings
Immersive Screen Mode is probably the worst option for VRto3D, as it zooms into the center of a large virtual screen. Be sure to turn off all the Curve settings

vorpX has built in gamepad emulation
If you own a XInput gamepad you can use it to play any game with the pad instead of mouse and keyboard
The gamepad emulation can be configured for each game in the in-game menu

These are a few lists of games that support Geometry Reconstruction mode, but none of them are likely complete