Which DMT stones do you recommend for a bow hunter to use to sharpen broadheads?

We would recommend one of our double sided DiaFolds.

If the blade is in decent shape, the ExtraFine/Fine version should be good.

If they are in pretty rough shape I would recommend the Fine/Coarse

If you have a wide range of issues, I would recommend both a ExtraExtraFine/ExtraFine + Fine/Coarse.

https://www.sharpeningsupplies.com/DMT-Double-Sided-Diafold-P12C7.aspx

There are a ton of different broad head designs out there. Some require you to dissemble it first.

Here is an funny review/instructional video of our Diafold and how to use it.

https://www.youtube.com/watch?v=SBHAYvg7suo