>>7725226First of all I'll assume you're a male.
I'm not a niji expert but I think that they don't value raw abilities alone as much. This is just my speculation but I feel like their guideline for hiring is more on the lines of "Will this person fit where I want? Is this idea of a vtuber original and viable? Will people want to watch it?"
They did change the approach for nijiEN a little by trying to pick most people from the same circle of friends, but even then each girl has a different appeal and varying sets of individual skills. I do think that at least for the first male wave they'll be a lot more conservative and try to pick safe bets, if that's even possible.
My advice for you is, be genuine. For example if you can sing, don't show that off as something to be measured on an exam or something like that. Show them why you like to sing, what would you do if you could sing as a niji. Remember, they're looking for entertainers. Your abilities are worth nothing if you can't/don't want to entertain people with it. Do what you love to do, but most importantly, ask yourself if you wanna share that love with others.
Anyways, good luck bro.