In the Brahmanda Purana, we have the Lalitopakhayana section. And there we find Goddess Lalita Tripurasundari creating the entire creation from scratch. Every deities were also created from her during the process.
So, during that time, Lord Vishnu and Goddess Parvati both came from Goddess Lalita's right eye which is of the nature of Sun. So, this is an indication that Tattva-wise they are same or that they have similarities.
She is of the form of these 16 Nityaa Devis. Maha Shambhunatha praised
Her in many ways. Order of Creation. She extended Herself in both male
and female forms and continued the process of creation.
A. From the left eye, which was of the nature of Soma (moon) came
Brahma and Lakshmi Devi.
B. From the right eye, which was of the nature of Soorya (sun) came
Vishnu and Parvati.
C. From the third eye, which was of the nature of Agni (fire), came
Rudra and Sarasvati.
Also, note that Lord Vishnu and Goddess Parvati are also mentioned in scriptures as brother and sister. .