Any help with learning English to Japanese vocab?

There is nothing bad about using WaniKani vocabularies outside WaniKani’s SRS timing system.

English-to-Japanese can be done too, for example,

However, I doubt you really need to always see or think of English words before making Japanese IRL. Also, much of the time, English words do not translate to Japanese well, or have various translations of various usage.

Nonetheless, I think English-to-Japanese memorization is good for kickstarting Japanese vocab’s pronunciations, because of no hinting of Kanji, nor Okurigana, at all. An easiest way to do this is perhaps [Userscript] Self-Study Quiz.