This platform claims to use the "diglot weave" method of mixing native language/target language vocabulary, and claims that they have Japanese options.
However, there are no samples to try, and it costs (at time of posting) $18 to buy a book credit. I feel very skeptical that you could do a low-effort diglot weave English-Japanese translation, or any other language pair that has a high degree of grammatical difference. You can't really gradually translate a sentence from English to Japanese outside of replacing common English nouns and adjectives with Japanese, or translating the entire sentence. Anything in between would be a total hash, and probably counterproductive to learning the grammar constructions. I'm sure most people here would share my skepticism about this method.
That said, has anyone tried it? Has it been effective for you?
by mountains_till_i_die