All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
In principle, there is nothing wrong for a husband to discuss sexual matters with his wife.
However, doing so while he is far from her, or showing their naked pictures through social media, involves Islamic violations, including inciting one’s lust, which may lead to searching for an illicit way to satisfy them.
On the other hand, these means are unsafe; other people may hack your account and see your conversations or pictures.
Therefore, you must avoid all of this and look for a means which enables you to reside together, either in your country of origin or where you work. This way, you keep yourself chaste and keep your wife chaste, and if you are blessed with children, then you would both cooperate in upbringing and nurturing them.
For more benefit, please refer to Fataawa 83038 and 81689.
Allah knows best.