What gear range can I achieve with the SRAM RED eTap AXS rear derailleur and a 2x crankset?

With a 46/33T crankset paired with a 10-36T cassette, you achieve 502% gear range with a sub 1:1 gear ratio (.92). With a 48/35T crankset, you have a 494% gear range yet still reach sub 1:1 gear ratio (.97).

With a 43/30T Wide crankset and a 10-36T cassette, you achieve 516% gear range, with a 0.83 gear ratio on the small chainring and largest cog. 

You can read more about SRAM X-Range gearing here.