Many people know Loxx for their guitar strap fasteners. What do you think about using a stainless steel version for an efoil hatch outside the gasket loop ? The top part would be recessed in the hatch thickness. The hole would be big enough to allow two fingers grasping it.
https://www.loxx-produkte.de/images/schaeffertec/SchaeffertecLOXXcatalogueKatalog2020HR.pdf
I dont think they will provide the compression necessary to keep the water out if you fall or submerse the board when starting
The compression depends on the gasket elasticity/quality, especially if it is a tube. The Loxx idea comes from a guy who is using them to attach his footstraps on his foilboard. He makes frequent jumps with this solution. The good point of this solution is that you can adjust the hatch eight therefore the compression by “just” rotating the male part screw.
The issue with these is that the hatch needs to compress past a certain point and then it will release very slightly. It’s the mild release that’s an issue.
With an efoil you want the hatch to stay at that maximum compression at all times thereby guaranteeing the seal. Twist latches means it is pulled down tighter than if you compress with body weight.
Then there’s also the issue of guys compressing with body weight and bending masts etc…