Who turned the clock?
Is it Groundhog Day again?
First of all: The (endless) debate about the 'amp-in-the-room' sound vs. the more 'mic'd recorded sound' filled this forum years ago already -
(and leads systematically to
An amp in a room is an amp in a room and logically will always sound different than a FRFR system (maybe more like an - amp in a room?). Maybe you should switch to a tube amp (Line6 DT series for example)?
Nevertheless, with (Global-) Eq's it's no longer a problem to tastefully influence the more high-frequency sound of a FRFR system. This is NOT a question of IR's in the first place. Both ways lead to good sound results - but they HAVE to sound different (because you are using different hardware, speakers etc).
Besides, Jason Sadites made this informative video (last year):
Eagerly awaiting a more detailed description of your (hardware) setup and your recording ;-)