Ironically, since I've been learning Japanese for a couple of years specifically to play this, the translation is one thing I'm not worried about. If only I had a trustworthy source for the demo...
Sigma grindset right 'ere
you can already convert rpg maker vx ace to mv there a video on how to do that using a script on ace playtest the game which will activate the script that will turn the data into mv ones and make a new folder then you make a new game with mv put the data there copy over the audio and the worst part would be to scale the character tiles sets faces and what ever else to mv sizes oh and find all the scrips paradox uses in ace and find the mv ver of them if they exist i wouldn't know how to make them for mv, after that you have monster girl quest paradox in mv
This is really something more for the Devs of the actual game than random fans. I wouldn't be caught really trying this on your average Indie-dev VX Ace game, let alone one of, if not the biggest, RPG Maker VX Ace game I've ever seen, with actual Post-game Randomly-generated (via script ofc) content and the likes.
Just for an impression (and to make the Mods for the game that I upped on my blog), I opened the game in the Editor, and fucking god damn this shit trucks slow, and I've got a decent gaming rig too at that (clearly not something to have VX Ace editor cry out of all things).
The sheer size of the game would make the conversion method insanely lengthy, even if we were to assume easy parity between Scripts and Data (since you'd still have to upscale the visual assets, and just those files are the very bulk of the size of the game), but not only that, there actually ISN'T perfect parity between VX Ace and MV Scripts. Not only did they change the programming language between them (went from Ruby to Javascript), but they also changed their game libraries, meaning that even if you were to use a converter online between the programming languages, you'd still have to ALSO replace all the instances of method/object/variable calls that are changed between game libraries, and then STILL test all of it out, as even if it sounds clear-cut on paper, in practice you'd still get at least a decent number of bugs PER script.
In short, by the time somebody would succeed in converting the current Demo only to MV, the Translation for all 3 Parts would already be out, and very likely the MGQ2 would also be well underway in its development, if not already released.
Unless, of course, you assemble a team for this conversion, that could cut down on time somewhat.... But it would have to be a very competent team, and patient one at that.
That conversion would also require its own translation, so even if somebody were to want to try this out, best bet is to wait until the Translation for all 3 Parts is fully finished, and convert the Translated game instead.