I perpetually swing back and forth between seeing a certain person or situation in a negative or positive light. It's like I can never pinpoint what it actually is, so I'm left to infinitely micro-tune my image. Furthermore, Ne ignoring makes it so I have difficulty accepting the existence of multiple POSSIBLE perspectives at the same time, so you bet the perspective I end up landing on has been thoroughly thought through (lol @ english) which leads to stubbornness/close-mindedness when it is challenged. Then, if I do end up changing my mind, I usually swing in the opposite direction, which is back to what I said in the beginning.
I don't know, this feels like a strange question to me because I feel like what you SLEs do best is bring us to Earth without meaning it. (I speculate it takes awhile for my ESI-Se mother to convince me of her Se statements because I sense her lack of Ti/Te authority. However, due to her Se-ish persistence and confidence, stuff ends up getting through eventually

)
I suppose the IEI has to recognize the strength in considering [your] Se/Ti/Te perception to begin with which can be a previous exposure thing. If they don't, well.. it comes down to how much do you care about them to help cause then you're gonna have to be persistent (because duality and your dual's perspective can be initially bitter) but I think it'd work out if they're reasonably mature (or is that me being optimistic haha)
I think blunt matter-of-fact statements would work. Point out the "relevant info", give a few gentle reality slaps (reality pats? pokes?). The way a SLE would say it would at least sow some seeds of doubt in their minds even if in the moment the IEI dismisses/rejects it.. leave to ferment for a few weeks & who knows, they might end up critically re-evaluating someday. I personally have this processing delay where something someone told me will all of a sudden pop up two weeks later with newfound importance.
But also.. how good is your relationship with the IEIs in question? What you can/should do also depends on that. I don't know if you're talking about big or small situations? --are you talking about everyday actions to help them or of how to approach a big Let's Talk About This moment?