hear the axe rx as you would a real amp, using frfr.
this is the same issue we've discussed in a previous thread.
the exact equivalent of using an IR is putting a real speaker cab in another room where you can't hear it at all, mic'ing it up and sending that signal to an FRFR speaker. that is the exact equivalent.
IR = real cab in another room mic'd up
you can't get the signal from a real guitar cabinet in another room into a FRFR speaker without a mic. there's no "direct output" on a speaker cabinet. it has to be captured somehow, and that somehow is a mic.
i understand the essence of what you want. but even with a real amp, there's no way to get a real amp and cab "into an FRFR speaker" without a mic. right? how would you get the sound of that speaker cab "into" the FRFR speaker?
what you want is for the signal coming out of the FRFR to be the exact same you'd hear standing in front of a real guitar speaker cabinet. but the way to do that is to use that real guitar speaker cabinet and listen to it in person. how can you capture the sound of that speaker without a mic? there's just literally no physical way to do that. it's the same way that you can't take a picture without a camera. something has to capture the image.
years ago, the IR capture method preferred using expensive "flat" mics that didn't add any coloration to the IR capture. from there, we could use the Mic simulations in the various gear to add a SM57 eq if you want.
although this sounds like exactly what you're asking for, in practice, it a) didn't sound like you were standing in front of the real speaker and b) took longer to mix because you had to add mic sims.
the industry pretty unanimously shifted to capturing IRs using the mics and positions you'd actually use in a recording session, and this is agreed upon by many as the superior method.
a big point you may be missing is this:
a microphone listens to one spot on one speaker, very close to the speaker. your ears are several feet away, listening to multiple speakers in the cab (assuming it has) at once, and also hearing the sound bounce off the room you're physically in at that exact moment. THAT is what "amp in the room" is. the physical space and actual volume perceived by both your ears at that moment.
a single FRFR speaker in front of you cannot make you feel like sound is coming from behind you. there's physically no way for a sound in front of you to appear like it's "bouncing off the walls" around you... unless it's actually loud enough to bounce off the walls around you. otherwise, now we're talking about Reverb effects.
this IS an issue that comes up often, but mostly because of the misunderstanding of how an IR works and what it is.
an IR must be captured by something, and that something is a mic.
it's been agreed upon by many that the mic to use is a mic you'd normally use (SM57, MD421, etc.).
a mic'd speaker cabinet is typically a single point on a single speaker - it is not an "amp in the room sound", therefore an IR typically cannot produce an "amp in the room sound." (far-field IRs exist, but still probably won't give you want you want.)
to experience the sound of a guitar cabinet, you must use a guitar cabinet. you can't model all 3-dimensional aspects of a multi-speaker device with an IR capture flowing through a single quiet FRFR speaker. the issue is not that a mic is being used. it's plain physics.