yes, that is definitely achievable, and I've seen some good honeycomb looking ones that doesn't look like they're made for chicken coop. You will have to consider the fact that it looks like there are plastic fasteners around this hole and if they can hold the metal mesh. I wish you were...
From what I learn, 3D filament is not as durable for outdoor use; though I have seen some people make them anyway. Also the nature of filament-style printing, you see a lot of textures that can easily catch dirt unless it gets body filled and sanded to remove the pits. It isn't as economical...
there will most likely be some consequences that has to be balanced. The solution I'm proposing is to cut down on the chance of rocks going into that tunnel with some kind of honey comb cut pattern plastic
I can probably make something for you out of plastic, if it means to just cover the hole with some kind of grill to cut down on the rocks getting in... I don't know how small the holes should be but I can research it.
I am currently in the process of designing my own rock guards for this car...
Took some near final measurements and evaluating the length for spacers to add for the guards to look flush, rather than sunken in with the wheel liner. Where the plastic fasteners are located, they are indented inward as well, not sure why Lotus do that type of thing, but that's accounted as...
is your suggestion about using magnets is because you don't want to drill into your wheel liner? I would like be interested in making some for the community and will take in any suggestions on what they want to see out of a set of rock guards.