Each method has features in which context to use it.
No, it's not grammatical. Nor does it make any sense. It's a garden path ending in a trackless maze. The way to tell this is to try to unwind all the rules that have been applied to fold the sentence into this shape and see where it comes from.
The first four words cause no problems, but in which context to use it is a horrifically complex and ill-constructed constituent. Technically, it's what's called a Relative Infinitive, and it's been further modified by having a relative pro-adjective which modifying another noun context, which is the object of a preposition in.
And that whole preposition phrase has been Pied-Piped to the beginning of the infinitive, which lacks a subject, so one needs to be determined, in order to understand the sentence, along with an antecedent for which, and a coreferent for it, the direct object of use.
In other words, something like the skeleton of the relative clause might be represented as
... features, such that [someone] uses it in which contexts
The [someone] is just an ordinary indefinite, no problem with an infinitive. However, what's it? -- it's singular, so it can't be features. Then does which refer to features? And what the hell is contexts doing there? You can't say *in features contexts. You can't even say *in feature contexts and expect it to mean anything here.
I could speculate about where this all came from, given the sentential context, but this seems clear enough. Or unclear enough.