The word "Ziyan" (زیان) is used in both Persian and Arabic, but there is a significant difference between the two languages in terms of pronunciation and meaning. In our context, the word is generally used according to its Persian usage. As you have asked in your question, "Ziyaan" (زِیان) (with a kasra under ز and a fatha over ی, without a shaddah) means loss, harm, and damage. It is therefore not appropriate to use this as a name.
In Arabic, however, "Zayyaan" (زَیَّان) (with a fatha on ز and a shaddah with a fatha on ی) can be derived from zayn, which means beauty and adornment. On this basis, the meaning of "Zayyaan" would be one who is extremely beautiful or full of adornment. With this pronunciation and meaning, there is room to use it as a name.
Allah the Almighty knows best.
Darul Ifta Al-Ikhlas, Karachi.
القاموس المحیط: (1204/1، ط: مؤسسة الرسالة)
الزينة، بالكسر: ما يتزين به۔۔۔وزانه وأزانه وزينه، وأزينه، فتزين هو، وازدان وازين وازيان وازين.
مصباح المنیر: (261/1، ط: المکتبة العلمیة)
زان الشيء صاحبه زينا من باب سار وأزانه إزانة مثله والاسم الزينة وزينته تزيينا مثله والزين نقيض الشين.
فیروز اللغات: (ص: 800، ط: فیروز سنز)