It happened the same to me, at the beginning.
What I did was to study Bunpro Vocab (Bunpro N5) with the Wanikani method, for words written in kanji (900 aprox).
When I started Bunpro, I was at level 10 in WK. If the Bunpro Vocab have kanjis, I learned the kanjis in Wanikani -it didn’t matter if it was of a higher level-. I learned the mnemonics for the composition of the kanji, to be able to identify it, and the mnemonics for the reading of the Vocab -it was usually the kun’yomji-. I didn’t learn the other reading, I’ll do when I reach the level o when I come across ca word with this other reading. From these 900 words, 730 have kanjis from 1-20 levels of Wanikani.
From these 900 words in kanjis, you can study 750 words in WK. I learn the kanji composition of these words in WK, it didn’t matter if they were from a higher level. For the words not in WK, I made my own explanation of the composition, it was easy because I knew the kanji meaning.
It may be because I started learning vocab with Wanikani, but for me, to learn words with kanji, I need to learn first the kanji -recognize it, its meaning and reading- and then the logic of the kanji composition.
There is also about 130 words in katakana. It helps me to know the word and the language -it’s not always English- they came from.
About 80 words in hiragana, mostly adverbs, expressions, grammatical particles. You’ll have to make your own mnemonics or associations with the readings.
This method has helped me a lot, because for me the WK method works, so it also works with Bunpro vocab.
The only problem is that you can’t add to your reviews in WK the kanjis or words learned ahead of your level. As a result, when I reach a new level in WK, I already know about 25% kanjis and 10% words. It helps a bit.
For these kanjis and words not in the WK reviews, I add them in another SRS for an extra review - not only Bunpro-. I use Kamesame - KameSame, but can be Anki or any other one.
Has it been a problem for my Wanikani progress to learn kanjis and words ahead of my level? Not in the least. I am currently in level 29. Of course, I had to learn some radicals out of the WK planification, but on the matter of radicals, I think that the sooner you learn them, the better. I’m talking about the real radicals, not the make-up radical compositions of WK, but if you know the radicals, you’ll understand this WK radicals.
Bunpro Vocab N5 was also a surprise for me, but it has helped me a lot. Because there was the appropriate vocab for a beginner, the basics words one must learn with a new language. It helped me to feel Japanese more real, more approachable.
WK is designed for learning kanjis, and the best way to learn kanjis is through words. So, in WK we learn a lot of words, to reinforce the different readings and meanings of a kanji. For example, from 1200 words in WK levels 1-10, only 500 words are N5, 200 are N3, 150 are N2 y N1.
Bunpro Vocab has sentences -with audio-, sentences with different levels. Vocab N5 has N5 sentences. Sentences help to learn words in context. They are perfect for mining. I used them to reinforce the grammar I was learning. WK can’t give you this, because it is not designed for this purpose.
I hope this could help you.