How to create a custom extra study set?

I don’t know the existing scripts well enough to say if you can get exactly what you want, but you can use the Self-Study Quiz for extra studying of items under a variation of conditions. The Item Inspector also helps with narrowing down things to study, such a visually similar items. But, as for similar readings, while not being a studying script but rather an additional information scripts, I really suggest installing the Keisei-script to get a list of kanji with the same radical and possible same readings during lessons. :eyes:

Now, as for the general premise of your comment, I think you’re overthinking things. While it’s good to have multiple ways for recollection, what WK is already doing is plenty to memorize kanji. But, to get a truly deep path for recollection, what you need is exposure to native content, so reading, watching Japanese TV, listening to Japanese podcasts etc is best.

Route memorization can only get you so far.