Source
The information was released at the same time on both the official KR website for Counter Side and the official JPN one.
Transfer
Currently, Nexon is publishing Counter Side in both the KR and JPN regions, but this will change in February 2023 as the publishing rights will transfer to StudioBside, the developer who created the game.
An extensive FAQ was posted about how this will happen, but it boils down to a transfer code similar to how you had to link your mobile and Steam accounts on Global. Your current progress in the KR or JPN server won't be lost and you will be able to play the game normally just like you do now but under StudioBside, not Nexon.
Since the transfer won't happen until February, we won't be translating the FAQ yet and will do it closer to the transfer date.
Implications
With StudioBside self-publishing the game in KR and JPN, on top of the Global server, we can expect the new servers brought under their umbrella to thrive as they did a really good job in Global. Now, they will have more freedom in deciding the future of the game, as there's nobody who can influence them, which is a huge win.
Also, it seems that all the promotional videos, webcomics, and music were already created and fully funded by StudioBside, and not Nexon, so don't worry - not only they will keep releasing quality content, but they also promised to release even more of it! This was confirmed in a Tweet by the director of StudioBside himself.
If you haven't watched the latest PV that was just released to celebrate the upcoming end of Season 2 of the story, check it out here.
Other servers
Now that KR, JPN, and Global servers will be handled only by StudioBside, we don't know what will happen with SEA, TW, and CN servers.
SEA and TW servers are currently published by Zlong Games, but they are releasing Archeland soon (Prydwen will also cover the game!), so who knows what will happen in the future! Let's wait and see.