The word Sophocracy, from Greek Σοφοκρατία:

σοφός (sophos) = sage, wise man
κράτος (kratos) = rule

Basically the rule of the wise men/sages (opposite of Democracy, the rule of people).

I need this word translated into Chinese, Sanskrit and Pali. I searched endlessly, but I just don't know how to translate it with certainty.

For Chinese I came up with 聖哲統治: 聖哲 = sage, 統治 = to rule.
For Pali: munipabhutta (based on democracy = pajāpabhutta, except muni = sage, wise man)
For Sanskrit: munitantra (based on democracy = prajātantra)

政治 strikes me as a better choice than 統治. Cf. 老人政治 "gerontocracy", 寡頭政治 "oligarchy", etc. 哲人政治 gets a significant number of Ghits, many of them in conjunction with 柏拉圖 (Plato), so I assume this is a conventional translation of "sophrocracy".

Can't help with the South Asian terms.

Well Plato used the term Noocracy, which means "the rule of the mind" i.e. "rule of the intellectuals". This is different from Sophocracy which is not a rule of mere intellectual people but actual sages. Noocracy in Plato's words would be the rule of the philosophers (those who love/search for wisdom) while Sophocracy is the rule of the sages (people who have wisdom, are wise).
So maybe 聖哲人政治 then?