Credit goes to @buttcheeckswizard on twitter

Literally every fighter is in full body spandex

Not officially in "mech suits" but I've noticed several female anime characters controlling any large mechanical device end up in some sort of similar pose eventually.
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Just as examples:
Kallen from Code Geass ends up in a bunny costume in a similar pose iirc. And I consider Code Geass pretty tame for it's fanservice
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All the female pilots from "Expelled from Paradise"

I mean Darling In The Franxx is an extreme example, but that whole deal is largely metaphoric

Pacific rim is a great example