They're Vtubers, but that's where the similarities end. Vshojo is made of already-established Western Twitch and YouTube personalities who decided to pool their talents together.
Also, Hololive is plenty naughty already.
They have naughty girls but isn't Melody a virtual pornstar?
Plus, I feel like Vshojo is generally more overtly lewd than a lot of Hololive. Silvervale even accepted the nickname of "Hornylive."
In my mind, Hololive is "coworkers who quickly become friends", whereas Vshojo is the opposite in that "friends who decide to start a business together".
The difference between Hololive and Vshojo is quite big. Hololive is a company hiring girls to work for them and they have a lot of power over what they do.
From what i gathered, Vshojo is a company specifically made by Melody and her group because most of them were getting big enough that they needed some kind of legal instrument behind them to deal with legal things, taxes etc so they decided to grab also 2 of their friends starting their vtubing careers and build it together because it's convenient to do it like that. This also means that girls have more power over their things because company works for them, not other way around.