I agree. I don't think Meliha will be the new Neriman. To me she loooks like a balanced OH neither defensive nor offensive. Of course her reception and attack are not great right now, but she is young and can develop. About Seyma I agree, she looks rather defensive to me. She lacks power in her hitting
I call Meliha an attacking OH because her serve reception is bad. I would call her an overall OH but from what I see earlier, learning to receive a ball is much more difficult than learning to attack properly. Considering her size (188cm) and age, Meliha should rather focus on improving her attacking rather than receiving. Besides that, she has been used as an OPP last year in the NT time to time which approves that she is clearly not a prospect for being a defensive OH. On the other hand Seyma was used in Eczacibasi as a sub for receiving when team was failing and for serving and she did a decent job.