Multiple exposures on negatives...hurr, that's not going to work, film doesn't work like that, you'd need to take separate exposures, digitize them and HDR them to get the same effect, well, any effect, exactly the same as digital.
But why would you want to, HDR was developed to improve the dynamic range of digital photos to match film, but y'awl went a bit mental with it, so your licence has been revoked

But hey, whatever, this isn't a film v digital discussion...and I'm not arguing for or against either, so why are you ?
probably not doing Tonymk any good either