>>54730970Nemona, Leon, or Red. The first two because of power-creep and fighting autism, and the latter because he's the OG.
As to what they feel like? Universally, the aura of any powerful trainer that's hostile towards you or scrutinizing you will probably feel like needles on your skin, or energy in the air that makes your hair stand up.
As for Champions? If they're a type specialist you'll probably sense small sensory hallucinations start to manifest based around their types. Wallace's might push an image into your mind of an intricate and beautiful underwater scenery. Lance, the maw of a dragonoid opening behind his person, to swallow you or to release a blast of pulverizing force. Steven might conjure glimmering stalagmites in the air, or the image of an impenetrable and perfect titanium wall, or stuff like that.
Champions more diverse in their team like Cynthia or Blue might unleash an aura more personalized to their vibe. I want to say Blue will literally glow blue, though there could be another layer to the color, like it's the vast blue of the sky that smothers you if you contemplate it for too long, or the gentle blue of dawn breaking conjured up behind him, washing everything a darker shade of blue or something. Same with Red.
Anywho, depending on the level of strength of the beholder or the intent of the trainer these could be quick hallucinatory flashes or full on impressions that make you shit your pants and paralyze you. Or they could be nothing at all, if they don't feel like flexing their aura.