I agree with HonorableTakoyaki's suggestion. A brief moment of Heiroe to try and catch up of what's going on (being in someone's else perspective) should help.
Otherwise, just note this is someone else's perspective in your writing and translate that visually when you draw this later (I'm assuming this is the same comic idea you were talking about). It could be possibly be drawn like an inner Sakura or ghost-form behind the "someone else" or some other abstract visuals.
Color-coding might work too if Heiroe and the "someone else" is primarily color-coded. For example, if everything is normally full-colored, then shifting to someone else's perspective may just be colored pink like some rosy-tinted glasses.
There's probably other visual notes to shift the perspective, but you'll have to play around to see what works for you. If you remember any media with a similar magical vision change, you can try studying how they depicted this to the audience. Like in Antman 2.