I mean...if the english subtitles on the announcement trailer are any indication...
That's not necessarily a confirmation. There have been plenty of release teaser trailers for localization that never came to be either due to money reasons or if the company decides there is no fanbase in the West to market to.
In fact, both Sega and Atlus on their English websites(not the .co.jp ones) have had a bad reputation of teasing releases in japan that never make it state side.
Their trailers also have a ESRB or PEGI notice on them, at least indicating they've felt confident enough to have started their paperwork through them. They also pulled the move of simultaneously releasing 8 versions of the game trailer for VC4 with hardsubs of Chinese, English, French, German, Italian, Japanese, Korean, or Spanish at the time they announced the existence of the game.
Interesting portion taken from the Playstation.blog link, which is from a short interview with the producer of VC4 Mikami Kei
What brought you back to the world of Valkyria Chronicles 4?
Kei Mikami: The aim of this Valkyria Project is to expand the series on a global scale. We haven’t released a mainline title since Valkyria Chronicles 3 in 2011, so our goal from the beginning was to attract new audiences worldwide. Our overarching vision is to return to the original Valkyria Chronicles’ roots, while building on improvements from the rest of the series. Valkyria Chronicles 4 is the culmination of everything we’ve learned up to this point.
We began setting the groundwork for this project with Valkyria Chronicles Remastered for PS4. Our intent was to let fans experience Valkyria Chronicles’ origins and core gameplay on a next-gen console before moving forward with a brand-new numbered entry to the main series.
What inspired the story, characters, and setting?
Kei Mikami: Valkyria Chronicles 2 and 3 were both released exclusively on PSP, which was a very prolific console in Japan. Their themes, therefore, catered to our Japanese audience, such as a schoolyard environment or a fantastical special ops team. This time we decided to return to the first game’s grounded military setting. As such, we moved away from super soldiers with extraordinary powers. Instead you’ll find characters who are more like people you could see yourself meeting in everyday life.
We gathered reference material by studying countless records of the troops who participated in World War II. In doing so, we learned about soldiers who never lost hope, even in dire straits. Perhaps it was their youthfulness that allowed them to hold onto that positivity. These tales of soldiers whose dreams were crushed by the stark realities of war, only for them to stand back up and face that reality head-on, affected our team on a deeply emotional level.