I started WK as more or less a “dead beginner.” I’d learned Hiragana and Katakana, and I was trying to dive into some grammar resources, but I kept getting hung up on furigana-less Kanji in the resources I was using. I felt like trying to learn the sentences and vocab and grammar while simultaneously recalling all these diverse and unrelated kanji without a foundation was too much.
So I started looking around the web, and found a opinion piece by a guy who suggested: If you want to learn Japanese, learn all 2,136 Jōyō Kanji before you even attempt grammar and vocab.
I thought to myself, you know what? Sure. I’m really struggling parsing these example sentences and grammar points because of the Kanji, so why not just nip that in the bud and come back to grammar when I’m done? I think this guy has a point.
I stumbled across WK trying to find a good Kanji-learning resource and instantly fell in love. It’s SRS (which I knew from research was a really strong method) but spoonfed to you to make it even easier. I bought a year pass almost as soon as I hit level 3.
Now, having studied WK for the better part of half a year, I don’t think I’m going to fully commit to learning all the Kanji “before I even attempt” grammar. After I hit level 6 on WK, I started watching Japanese Ammo with Misa and Japanese From Zero on YouTube. Also, I’m doing KaniWani and the kana-only vocab SRS on Torii (which is fantastic). I’m also picking up Genki this month, and slowly but surely easing my way into shadowing and speaking practice.
TL;DR: Starting with just WK is fine as long as you can comfortably read Hiragana. You can get into grammar and speaking/listening practice at your own pace.