I regularly do smaller chamfers than that, 0.1mm or 0.15mm are pretty common on a lot of my stuff, really not much more than a de-burr really just to clean up the part
I mostly use a standard 6.0mm dia 4 flute solid carbide chamfer mill, note I said chamfer mill and not chamfer tool, easy enough to get a chamfer mill way down to 2 or 3 millimeter dia. I always set the chamfer as a “depth” and set the tool offset in the chamfer feature to 1.5mm, this will put the edge of the material halfway up the angle of the chamfer mill. The only criteria regarding the chamfer mill is the depth from the top of the material to the bottom of either the material or the fixtures/bed, usually the diameter of the tool isn`t a problem as you can set the tool higher or further out to clear obstructions just by altering the offset value in the feature.
I don`t have BobCAM for Solidworks but I would think that the tool library would be the same or very similar to the V25 I have and I would expect the Chamfer feature to work the same