Yes, the G29 and G920 are practically identical. Both are PC-compatible, with the only differences being console compatibility and the G29 having and extra couple of buttons, LEDs and a dial on the wheel. The G920 has XBox labelling on the buttons (A, B, X, Y etc), the G29 has PlayStation labels (triangle, square, circle etc).
They're both very well supported on PC racing games as they probably the most popular wheels out there (although my brother had to use the G920 profile in Project Cars 2 to get his G29 recognised).