Mahābhāgavata Purāṇa Chapter 3, Verses 25–26:
Then from me that illusion oh sage, was born. The third one viz., paravidya is divided into five parts by herself such as Ganga, Durga, Savitri, Laksmi and Sarasvati. Absolute Nature told Brahma, Visnu and Mahesvara.
Savitri was welcomed by Brahma, and then Vishnu received Lakshmi and Sarasvati as His own share. Gaṇēśajananī Durgā was born as the daughter of Daksha Prajapati, and Ganga became Śambhu’s wife.
Comparison with the Devi Bhāgavata and Brahmavaivarta Purāṇas
In texts where Goddess Rādhā is listed among the five primary Prakṛtis, she is described as a direct feminine manifestation of Mūla Prakṛti, dwelling in Goloka.
Devi Bhagavata Purana Book 9, Chapter 1, Verse 1:
Śri Nārāyaṇa said :-- This (Highest) Prakṛti is recognised as five-fold.
When She is engaged in the work of Creation, She appears as :-- (1) Durgā, the Mother of Gaṇeśa, (2) Rādhā, (3) Laksmī, (4) Sarasvatī and (5) Sāvitrī.
The Mahābhāgavata Purāṇa offers a unique perspective on the identity of Goddess Rādhā during the Kṛṣṇa-Līlā. In Chapter 49, Lord Śambhu wishes to share deep devotion and companionship with the Supreme Goddess Kālikā. He asks Her to take a male form on earth, while he takes on a female form to become Her wife.
Mahābhāgavata Purāṇa Chapter 49, Verses 16-19:
Sri Siva said If you are really satisfied with me than you possesing male form visit the earth and I will be there in a female form. As I am your favourite husband so also you are my beloved wife. That is why I express my ultimate desire. So please fulfil it as you are the bestower of disered objects to the devotee. Sri Devi said O Lord Mahadeva for your satisfaction I will be on earth no doubt inmale form as Krsna in the house of Vasuleva. O Trilochana you must be a female for my love sake.
Mahābhāgavata Purāṇa Chapter 30, Verse 4:
Out of your own desire sometimes you become Sambhu by your portion. In the form of a woman the perplexer of the three worlds you enjoy yourself. Out of your own illusion you appear as Krsna a male and imagining Sambhu as your wife Radha you enjoy.
This non-dual exchange, where Lord Śambhu transforms into Goddess Rādhā as the Supreme Goddess takes the form of Lord Kṛṣṇa, is documented in major Tantric Shastras.
Sarvollāsa Tantra Patala 3, Verses 33–34
There was no contradiction or opposition between their words. At that very moment, that Supreme Power, the Parameshvari, assumed the form of Krishna. Seeing the feminine power take on the male form of Krishna, the Parameshvara assumed the form of Radha. Thus, it should be understood that the male principle arises from the aspect of Radha, while the power-holding female aspect arises from the aspect of Krishna. This is known as the mystery of creation, according to the firmly established Vaishnava view.
Specific to the Mahābhāgavata Purāṇa Kalpa: Rādhikā is Lord Śambhu (Puruṣa) assuming a female body to participate as the consort in Goddess Kālikā's descent as Lord Kṛṣṇa. Because She is Puruṣa in a feminine role, She is excluded from the original five direct female emanations of the Divine Mother, and Mother Gaṅgā is listed in Her place
Specific to the Devī Bhāgavata Purāṇa & Brahmavaivarta Purāṇa Kalpas: Rādhikā is Mūla Prakṛti Herself, and is therefore enumerated directly as one of the primary Pañcaprakṛtis.
Both perspectives make sense within their own contexts through the principle of Kalpabheda, showing that Puruṣa and Prakṛti are non-dual and can take on reciprocal forms in the Līlā.