If you're hitting shoulders twice a week/sort of three times including back-rear delts, you might want to tweak what you're doing on each day. For example, one day work them heavier/lower rep and the next go a bit lighter with moderate-to-high reps. Just more variety for more diverse stimulus.
I already guessed the male part, but thanks. How tall are you? If you're 6'2", it's quite a bit different than if you're 5'8".
No, to me it does not make sense that there's any way to target the "front or rear portion of the medial delt." As I said, there's really no such thing and if there were, the average shmoe in the gym (you, me, and most people on this site) don't need to waste the time or energy trying to improve it.
A general rule of thumbs for exercise selection is "whatever gets stretched most gets trained hardest." Lying on an incline bench will stretch the front delts more, so even if the weights are moved through the standard lateral raise ROM, the front delts will be firing more from the get-go.
Sometimes, just doing something different is enough to spark growth. So stick with the new exercise for a month or so and see how it goes. Another "something different" to consider is lean-away laterals.
Because of the sideways lean, momentum is basically eliminated and you're able to work the lateral raise movement through a higher section of the ROM due to the altered pull of gravity. (In a standard lateral raise, bringing the weights above shoulder-level would bring in more trap work, but because you're angled, the traps can't contribute as much.)