I don't think it's possible
if it is, I'm also looking for a way to do this
the jittering is caused by the delay between client send mouse movement -> server process mouse movement -> server tell client to reset angles -> client receives command to reset angles
also to OP try my code, set_pev is fakemeta and is much slower, this still isn't perfect but it makes the player move much less than with set_pev
PHP Code:
new Float:fAngles[3]
entity_get_vector( id, EV_VEC_angles, fAngles )
fAngles[0]= 0.0 // pitch
fAngles[1]= 0.0 // yaw
fAngles[2]= 0.0 // roll
entity_set_vector( id, EV_VEC_angles, fAngles )
entity_set_int( id, EV_INT_fixangle, 1 )
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