The GRX 800- series (Ultegra level) stuff would map to the SRAM Force stuff as far as lineup goes. The GRX stuff shifts better in front if you're going to run 2x and you can add a crosstop brake level. Those would be about the only differences.
I'm running Force AXS 1x on my main bike and my wife has GRX 810 Di2 2x on hers. Shifting on both has been flawless. The only complaint between the two is that I don't like the SRAM brake (big surprise). I have Force 1x Mech. on another bike and it has also been very good and the brakes seem better than the AXS version. I think both are very good and if I wanted to go 1x it would be SRAM and 2x I'd go GRX. You may want to check to see if you like the feel of the hoods on one vs. the other; I like the GRX design myself.
Those a really the extent of the important differences other than the shape of the shifter and the SRAM crank can run Direct Mount chainrings which look nice and can be really small - Shimano GRX can run a tiny ring too though. Shimanos BB86 bottom bracket is a bit better for BB86 frames (anything not called something 30 or 47)
if you get Sram with the DUB bottom bracket, use the SRAM bracket as they have special sized bearing.