I'm looking for examples of having 2 or more nouns in the same case but with the different semantic roles given by the differing referents of the nouns, not entirely by one of morphological case, syntax nor context. For example, the double accusative in Ancient Greek: "τὸν λόγον φῐ́λον διδάσκω" only differs in emphasis from "φῐ́λον τὸν λόγον διδάσκω" etc even though "λόγον" and "φῐ́λον" are classed as being in the same case, that is *something other than the case markers ('-ον') or the word order says that a friend is the person being taught and the reason is the thing being taught, rather it's the things themselves. Canst thou imagine a friend being taught to the abstract thing logic?*. Examples within Greek but using a different word welcomed.
Latin is full of these:
Illum meum amicum appelo. (I call him my friend)
Romulum regem romanum fecerun. (They made Romulus into a king)
This is with verbs of change (somebody changed/made into something), verbs of appelation (somebody being called something but also nominated to be something, similarly to the previous example) and verbs of considering/belief (somebody considered to be something).
The first example that comes to my mind is the dative shift in English, i.e. the construction found in the following sentence:
I gave John a book.
Both arguments are NPs (rather than PPs), so formally you can consider it a sort of "same case" situation. Both arguments can become Subjects of a passive sentence (The book has been given to John by me vs. John has been given a book by me), which makes them equally good Direct Objects.
Dative shift is a very debated construction: some scholars consider it derived from the canonical transfer construction (such as I gave a book to John), while others think that the difference in meaning between the two is relevant enough to view them as two independent constructions (see more on Wikipedia).
Another interesting construction is to be found in Russian, in a particular type of sentences with a dative Subject governed by an infinitive, with a deontic meaning. In case the predicate has also a recipient semantic argument, then the dative-marked syntactic arguments become two:
Не мне тебе объяснять
Ne mne tebe ob"jasnjat'
not I-DAT you-DAT explain-INF
"It is not up to me to explain it to you" (notice also the two PPs headed by to in the English translation)
Although frequently used, this construction can be still considered ungrammatical by some speakers.
Possibly this Hebrew case (with verbs of teaching and asking): https://forum.wordreference.com/threads/double-accusative.327943/