Because transliterations can differ, what's printed should be used in principle. So this should be mostly an issue for pseudo-releases unless Indian labels commonly print tracklists in Latin script.
This may be the case, but it almost certainly is so because of English being a very common language on the Internet. The guidelines for Japanese use this as a rationale for English-style capitalization. This could be used to support having similar guidelines for Devanagari transliterations, but I would rather change the guidelines for Japanese. I think sentence case would be the more neutral case when there's no standard. Of course, one can argue against it inherently being more neutral, and any actual standards would be much better to use.
From the Japanese guidelines (I haven't read the guidelines for other scripts :slightly_smiling:), we can gather some makeshift guidelines for Devanagari (which is the script used for Hindi, if I'm not entirely mistaken):
- If it is an official release, use the tracklist as printed. This comes as a consequence of the next point.
- If an official transliteration is available, use it.
- Otherwise, use a widely used transliteration.
The Wikipedia page links IAST, which is a "widely used standard", and Hunterian transliteration, which is adopted officially by India. IAST is a subset of ISO 15919, which as an international standard should probably be preferred.
As for the actual question, I don't have an answer I was hoping for one of the major transliterations to use capital letters in some other way, but it seems none of them define a case standard (from what I can read on Wikipedia). You could search for usage online, but I suspect you would find English title case mostly from the context.