I think Bodde is correct but will add that someone has posted a preset SITARSINSPACE which provides a sort of a sitary reverb sound. It’s a clever preset but let’s be clear that it is a reverb.
The EHX pedal might be worth a look as long as you are not a sitar purist. It might be the best simulation available.
I have seen two commercially available guitar bridges that intentionally induce string buzz to simulate sitar buzz. Again, no purist would go for that. Search the Net for details.
