Practicing going EN → JP is very useful if you want to be able to have conversations in Japanese and/or write in Japanese, and though WK doesn’t practice that, luckily there are sites where you can!
I recommend checking out KaniWani, which is the EN → JP version of WaniKani and requires you to input your public API key (which can be found here) to sync your WK info to get started 
There’s also a newer alternative that you can check out, KameSame 
