If Jane Schoenbrun is feeling the pressures of being their generation’s highest-profile trans filmmaker, it shows in only the most enjoyably defiant of ways in Un Certain Regard opener “Teenage Sex and Death in Camp Miasma.” A steamy stew of sex, death, VHS and junk food, as though workshopped by Eros, Thanatos, Colonel Sanders and the Jolly Rancher in the seediest recesses of a Blockbuster Video, Schoenbrun’s delirious third film is their most accomplished, most persuasive and most playful movie yet. Here, the director’s perennial questions around gender identity and identification are sublimated into a tribute to the slasher genre that also serves as an exploration of the frequently fucked-up nature of female desire and a manifesto for giving yourself the permission to feel it. That writer-director Schoenbrun has also designed their movie as a delightfully meta in-joke on the Hollywood studio machine, is evidenced by a terrifically overstuffed opening credits sequence.…