As a followup to the DOT-01 battery status, I found the last of the Wasabi NP-BX1 batteries in a drawer where they’d sat unused for eight months.
Recharge and test to get the blue lines, with the red lines from the DOT-01 batteries:
The double blue line came from a second recharge of that battery, just to see if more electrons would help. Nope, it’s still dead.
The Wasabi battery with the highest capacity also has the weirdly rippled voltage trace and, when I extracted it from the test holder, came out disturbingly warm and all swoll up. This is A Bad Sign™, so it spent the next few hours chillin’ on the patio and now resides in the recycle box.
The Smell of Molten Projects in the Morning 
I would be nervous about batteries channeling Japanese condiments myself. [ducks and runs]
For at least a while, “Wasabi Power” faced off with a copycat “Wasabi” brand. Now Amazon is flooded with seemingly identical batteries. I have no clue how to pick one over the other, particularly as buying a single battery costs more than half as much as buying a pack of two batteries with a charger.