Is not possible just slap a 36t cassette and ride with the big derailleur? That's what I do with 11 speed SRAM, don't even need to swap chains, just change wheels between road or gravel setup and adjust the b-screw. Bonus if you have the same hubs, otherwise you'll have to space the rotors to avoid centering the brakes every time.
Why don't you just try one cassette from the shop? 11 speed with the long cage shifts a lot better with the 36t cassette than with a 46t. Pretty sure I could still get a bigger or a smaller cassette as there's still some b-screw to play with. If anything, I'd expect AXS to shift better.
Is not possible just slap a 36t cassette and ride with the big derailleur? That's what I do with 11 speed SRAM, don't even need to swap chains, just change wheels between road or gravel setup and adjust the b-screw. Bonus if you have the same hubs, otherwise you'll have to space the rotors to avoid centering the brakes every time.