I think that preparing a snuff containing DMT and bufotenin is illegal, in the same way that preparing ayahuasca is illegal.
I personally would not mix the two for a couple of reasons. The first would be my lack of experience with both materials. I've had a stash of those DMT beans for years, but never did anything with them because the thought of snuffing that paste up my nose seemed unneeded (I am more interested in snuffing 5-MEO-DMT). Morning Glories I used twice when I was in my teenage years. Both experiences were partly failures. I had better experience with HBWR (although my dose was a bit low). Regardless, I don't have enough experience with either of them. Combining may just result in give me a cloudy trip. Next, I don't think LSA would mix well with the DMT compounds. LSA gives me a calming psychedelic effect. I can fall in and out of a nap and hardly realize. While DMT is a drug I prefer to use when I feel fierce, open, and aware. I think LSD is the only chem I will use DMT with. I've combined DMT with a variety of substances, but mostly LSD is the one that works best I think. With acid I don't feel drained when I come back down from the trip, as I do with some other psyches. With LSA, I usually feel fatigue anyways.
Hmm. On the other hand, perhaps the snuff would mix well the LSA. Perhaps DMT would mix well with LSA. May LSA's calming effect would produce a slower DMT trip (usually my trips are fast paced, a rocket to the peak, where I enter a place and waves of psychedelia wash over me before it all fades away. Maybe I would feel more relaxed in that come-up if I was on LSA. It's hard to say.
I'm out of my binging days. My last binge showed me that it is possible for me too get much stupider. The time is now to stop acting reckless. And so I've been cleaning up my act. It is hard for me to imagine combing most drugs anymore. I feel like when I started using psychdelics it seemed normal too just mix and combine em all. Ha, not so sure anymore.
Conclusion: If you do not have a few good experiences with each material, then you should not combine the materials. Without good prior experiences with both materials, you lack the proper know-how of preparing these materials, as well as reasoning for mixing them.
If you know both materials very well, and you feel an itch compelling you to get funky with your stash, then you should probably go for it. Be careful!