Function vtrnq_p16 

pub fn vtrnq_p16(a: poly16x8_t, b: poly16x8_t) -> poly16x8x2_t

Available on (AArch64 or ARM64EC) and (AArch64 or ARM64EC or target feature v7) and (ARM or AArch64 or ARM64EC) and target feature neon only.

Transpose elements Arm’s documentation