Contrary to sumwuns answer, I can say for a fact that The written language in Pokemon games bares no resemblance to Japanese. As someone who was taught from a young age by a native Japanese speaker, and proceeded to self teach throughout the years, I can confirm with every bone in my body that no signs in the game are in any form on Japanese. There are a few characters that resemble Katakana and Hiragana, but are plain, incoherent messes.
Although I do not remember where I heard this, in Gens 1-4 they did use real Japanese in the games and Anime, but since Gen 5 they made their own symbolic language that's gibberish for the sake of making it easier for universal releases and translations. According to this, The language, dubbed Pokelingo, used previously was able to be decoded as it was written based around English, but unfortunately the one in Sword and Shield is a completely different language as far as I can see. As for my observations in game, there seems to be two types of fictional language in Galar, and so far, it seems to be copy-pasted in majority of places.
I ran throughout the game like a madman and noticed a few consistencies:
-Every sign was the same (in regards to route)
-The symbols used in the gyms are different than the symbols used in the overworld and in houses, signs, etc
So they did try to add a variation to make it look more realistic, but from what I seen the majority of it looks to be copy-pasted.
From the knowledge we know and from what we can see, it is in fact possible that there may be a way to decode Galars Alphabet, purely based around the history of what they did in the Gen 5 Anime. But unfortunately, as for my observations, it seems unlikely as the majority of the text seems to be repetitive in multiple areas, making it unlikely, and rather that they have random assorted letters and signs premade and ready to be dropped into the game.
As of now, there is no known translation.