I don't think that MoeNovel would realistically, go beyond a cease and desist. For one, I don't think they'd seriously consider a cease and desist until they plan on releasing Cocoro@Function overseas. Realistically, I don't think they'd want to release Cocoro@Function overseas.
Conceptually, they'd literally be going against all their professed morals. Konosora has a heartwarming story. Cocoro@Function has cute interaction. The latter is not laden with the content which they aim to supposedly spread. They want to spread novels beyond the otaku stereotype. Cocoro@Function sort of caters entirely to that.
Economically, if they were to release Cocoro@Function overseas, they'd have to set the price reasonably. Everything within Japan is typically made exclusively within Japan. Most Western fans are not willing to pay market price for the raw novel. Visual novel companies know this, so they don't bother outside their demographic. They know that their fans would spend ~100$ on the regular edition, perhaps even much more on the collector's edition. They don't ship overseas [meaning, they don't consider the market much at all]. If someone were to buy something from Japan, then in most situations, they'd have to go through a proxy service. Cocoro@Function is not a cheap novel; it's got high-production value. It's also very new [which means that there's no point in releasing it overseas yet when domestic sales are still going on; cross-importing would be a dilemma].
Economically still, there's the legal precedence in actually pursuing legal action. In the eyes of a visual novel company, the overseas market is pretty mediocre. Most people have not heard of anime. Probably one a in a few hundred anime fans know what a visual novel is, and out of those, a fraction of those play them. Of that percentage, even less legally buy the game. MoeNovel would have to hire lawyers to pursue legal action beyond a cursory cease and desist [which does little than formally ask the party to stop].
There's the legal aspect of it. They'd have to prove without a doubt, that the party they're targeting is absolutely guilty. But this is the internet, where anonymity's prolific. They'd have to ascertain the identities of all the parties involved, allocate blame, and pay for a very expensive lawsuit.
It doesn't make sense for a Japanese company to pursue legal action overseas for a niche market that won't have much affect on its sales. They'd have to pay thousands in legal fees [as the bottom estimate], for the sake of protecting a few hundred dollars more in sales [visual novels don't quite sell overseas]. At the end of it all, if they even do manage to formally 'stop' the actions, there's no stopping the group from working in secret, or the translated script being 'leaked.'
I don't think that MoeNovel's that dumb. They're a company in the end. They won't pursue it unless they have enough to gain. Which in this case, is nothing.