I think is an interesting concept but good Shego always felt different than the other characters who also got their morality swapped.

Shego’s brothers were still silly and useless and didn’t know what they were doing, they weren’t that different from their good selfs, Ron has always had a dramatic flair and he has hidden depths in terms of ability he still seemed in-character and Drakken has always been a goofball so him getting along with Rufus and helping Kim isn’t that far fetched.

All of them still felt like the same character

The exception being Good! Shego, how can I described it?

lt seemed fake? Manufactured? She was too nice? And we know Shego was never like that Hego remarks how she has always been snarky even when she used to be part of team go.

There’s a few people who liked her as good, but it always bothered me that unlike the other characters, Shego didn’t felt like Shego at all. Do you get what I’m saying?

you're going to get a lot of how my brain works in this answer, lol...

first, we have to remember that the devices used in Bad Boy and Stop Team Go (and seen being tossed out of Drakken's closet in Dimension Twist) are two different devices.

the device in Bad Boy is Jack Hench's Attitudinator. it works by removing the wearer's good and bad energies, and putting back just the bad. or rebalancing, as he says in his commercial. what happened to Drakken and Ron was that Drakken's good and bad energies were extracted and split between them. also worth noting in the same ep, is when Drakken tested his badness level he ranked pretty low. i personally headcanon that he'd psyched himself out a bit and ranked a little lower as a result. also of note is that when Shego tested her badness level, she maxed out the scale. we'll come back to this later...

the Attitudinator caused Drakken and Ron to gradually change their good/evil bend, once again based on Drakken's good/evil parts. how much Ron's own evil side was adding to the influence of Drakken's evil, who knows... but Drakken was then purely good and it was his own goodness. i like to think Ron kept some of Drakken's influence after the incident was over... but to your point: their personalities still felt like THEM. maybe that's just how the device works? maybe because Ron still had his own good/evil along with Drakken's evil, and Drakken because it was specifically his goodness? (also, note the continuity error at the end of the episode when Drakken's badness goes back, it shows his goodness going to Ron. it should have only been the badness returning to Drakken and nothing going to Ron, but i'm sure they were just trying to visibly show that Ron is good again.)

anyway, this brings us to the Reverse Polarizer. it....reverses what the person already has, as is indicated in the name. and yes, this is a repurposing of Jack Hench's device, but Electronique changed how it worked. so theoretically if it directly reverses the target's goodness/badness... if a person is extremely bad, like Shego (evidenced by the badness scale) then when her polarity is reversed she'll then be...extremely good. so in terms of how the tech worked and how she presented...it does in fact make perfect sense to me. and that says a lot about Team Go and Ron, and the nature of how good and evil present... we could get into how Mego is egotistical and yet still inherently good, to be directly reversed like that. but even among Team Go, their personalities stay the same. all of their memories are intact. and when it happens again to Ron, he seems to be basically the same as when he was influenced by the Attitudinator.

so based both on the tech itself, how it works, and evidence of the other characters and Shego's own "good" behavior... i think it's perfectly in character. because this is Shego with her good/evil totally reversed. this is NOT who Shego was as a member of Team Go. because that Shego is the Shego we know.... she willfully chose evil over good. and if we take the badness scale as canon...that means Shego is pretty supremely evil (see what i did there, lol) and Drakken and theoretically the others...not so much. it might be that Drakken, Ron, and Team Go have a better balance of good/evil within themselves (Drakken's badness scale... he also willfully behaves in an evil way, even if the scale doesn't show much) while Shego has no balance at all, lol. now i do personally think she has some hints of good in her, but...yeah. all of this said...i think what they did on the show makes perfect sense.

the Shego who we know in the show IS the Shego who used to fight for good on Team Go. so the reverse polarized Shego...yeah it was her, but it was a totally altered version. not how she would actually be if "good." artificially manufactured good, since that's never been her.... while the others were probably much more accurate to their good/evil balance within themselves.

now....you CAN totally ignore the badness scale. and this explanation still holds up, since Shego has always been evil. but everyone else used to be good. as you said, Hego said she was always snarky and liked evil the more they fought it... but Drakken used to be good. Ron and Team Go are good. i think Drakken, if persuaded with enough fame and recognition, would consider going good... it fits with his personality and reason for going evil to begin with.

i think it all hinges on that Shego is inherently a bad guy. the rest were turned by the device. so they seem more themselves because...they aren't really changed all that much. but Shego was altered drastically because she's the most inherently evil of them all.