Dear Zdenek, what you say is borne out by my tests, where the only font showing a difference between Sanskrit and Hindi is the FreeSerif (the -kti- conjunct).  

(I used the Fontspec/Polyglossia system for language-switching.)

Best,
Dominik

On 18 June 2017 at 02:04, Zdenek Wagner <zdenek.wagner@gmail.com> wrote:
Hi all,

as far as I know the Devanagari fonts are either Sanskrit with all conjuncts that cannot be switched off or Hindi without the Sanskrit conjuncts. The only exception is FreeSerif which takes the Devanagari block from the Velthuis Devanagari and models the two modes from the "good old" Velthuis Devanagari, namely @sanskrit and @modernhindi. It was my suggestion implemented by Steve White. In all other Devanagari fonts language switching has no effect because there is nothing to switch, the language variants are not defined. I do not know how to do it, Steve White knows. I just specified the desired result and Steve did it. It would be nice if other font designers learned from his work.