This mod should be placed next to BBTAG.exe.
It will create a new file ONLINE_FRAME_DELAY.txt in the game folder, the default value is 1, but you can set it to whatever you like, any numbers in the 0-5 range probably work best.
To change the input delay after configuring it, a game restart is currently required (I wanted to add a UI but that requires hooking D3D9Ex, so hudhook doesn't work with BBTAG).