The Japanese product page for I am Setsuna (known as Ikenie to Yuki no Setsuna in Japan) reveals a little detail about the recently released Nintendo Switch version that has not been talked about in the West. The page lists the Japanese eShop version of I am Setsuna has having English and French subtitles, in addition to the Japanese subtitles as you can see on the last line of this screenshot of the product specification.
The translation for the last line is as follows (thank you to Benny Carrillo for translating)
対応(Software Support) 言語(Language)
日本語、英語、フランス語 (Japanese, English, French)
Given that this appears to be present on the digital version, it is likely that this also applies to the Japanese physical release as well, which would be good for importers as a physical English language version of I am Setsuna has been frequently requested by fans. If you are interested in purchasing a physical copy of I am Setsuna for yourself and wish to support oprainfall, you can get it via our affiliate link here.
I am Setsuna is available in the West as a digital only title for PS4, PC via Steam and Nintendo Switch. In Japan, the title is available physically and digitally for PS4, PS Vita and Nintendo Switch.