Why a convex edge? a "v" edge stays sharper, and is easier to touch up.
I agree about the original (alleged quote-unquote) "Edge" on a factory produced machette.
Tho admittedly my only experience is with a couple Cold Steel models.
Of the five CS machettes I have bought to date, the original (alleged quote-unquote) "edge" was useless. Would bounce off a green palm frond, laying on a board.
Lots of burrs, roughly a 70~90° inclusive "edge" bevel.
I used a draw-through "sharpener" to get rid of the burrs, reprofile the edge to ~30-35° inclusive, then use a file and stones to get the edge to roughly 25-27° inclusive.
I could use them to chop the fronds to 4' so the trash truck would take them, and to de-husk and open the coconuts I sold at a nearby sunday swap meet. (Yude be surprised how many coconuts 72 "lazy" and 1 "energetic" coconut palms can produce a month. One year the "Energetic" one produced over SIXTY a month ... almost the same as the combined production other 72 coconut palms we had on the property.
Trimming the fronds, and dropping the coconuts so they could not drop onto someone was a never ending job (like returning seaweed to the sea, and raking the beach daily, and pulling weeds between the paver bricks ... "Job Security". )
Start at one corner of the property, workway around the property ... in the week or so it took to get back to the starting oint, it was time to start trimming again.
We had twenty-five 35 gallon trash cans. The trash truck came weekly. I usually had 23 cans of fronds every week.

After Hurricane Dennis, I had a pile of fronds, seaweed and beach debre 20' foot wide at the base & 15 foot wide on top, 12 foot tall, and 90 foot (including a single 15'foot vehicle access gap) long for the trash company to haul away. Yes. The owner of that company was not very fond of me after that ... even though we gave him a thousand dollar tip ... in addition to whatever his contract with the County paid him. I guess I made he & his his grapple truck work too hard?