Do the time periods and stories overlap among these three scriptures?
The three scriptures that you have asked about present a lot of overlap between them regarding Krishna's life-story but there are also certain differences that I shall point out below.
Let us start with Shrimad Bhagavatam which is perhaps the most definitive of all scriptures on Krishna and forms the basis of Krishna worship in many traditions. The Tenth Book of Bhagvat Puran gives the life story of Krishna in detail. It begins with Parikshit's enquiry about Krishna's life in response to which Shuka Dev starts narrating the events leading to Krishna's birth starting from:
Devaki and Vasudev's wedding,
birth and exchange of Krishna
his childhood pastimes including the killing of demons (before and after moving to Vrindavan),
his pastimes with the gopas and gopis,
deliverance of Kamsa & defeat of Jarasandh,
movement of entire population to Dwarka,
marriage with Rukmini and birth of Pradyumna,
episode of the Syamantak mani & marriage with Satyabhama
other marriages with the Ashtabharya,
defeat of Narkasur and release of 16100 abducted women,
Krishna's grandson Anirudh's marriage,
deliverance of Nriga & others,
marriage of Krishna's son Samba,
Rajasuya Yagnya of Yuddhishtir & killing of Jarasandh, Shishupal, Shalva and others,
Sudama episode, meeting Nanda-Yashoda and gopa-gopis again, deliverance of Krishna's six brothers who had been killed by Kamsa,
marriage of Subhadra & Arjun
visiting Vaikuntha with Arjun
Samba and other boys cursed by rishis,
Krishna's departure from earth
As you see most of Book 10 is related to Krishna's life that is beyond his role in the Mahabharat but there are certain portions that are relevant to that particular epic which I have highlighted above. Also, Book 3 of Bhagvat Puran covers many aspects related to the Pandavas and mentions about Mahabharat War happening since the protagonists are related to Krishna.
The Mahabharat on the other hand is more concerned with the stories of the Kuru clan rather than that of Krishna. Shri Krishna features in the story wherever he has a direct influence on the events happening in the main narrative for example the Draupadi Swayamvar, abduction of Subhadra, the Rajasuya Yagnya, Shanti Prastava to Kauravs etc. but he features especially in the Bhishma Parva where he gives the discourse on Bhagvad Geeta.
The Harivansha covers most of the same incidents as the Bhagvatam viz:
Narada’s warning to Kamsa that sets a chain reaction
The birth of Krishna and his exchange
killing of demons
migration to Vrindavana
the death of Kamsa
education of Krishna and Balarama under Sandipani and the rescue of his children
attack on Mathura by Jarasandha and his defeat
meeting of Krishna and Balarama with Parasurama; the ascension on Mount Gomanta; the burning of Gomanta
migration from Mathura to Dwarka
Kalayavana’s attack on Krishna and his death
slaying of Narakasura
marriage of Pradyumna and the slaying of Shambara
the tale of Krishna's other son Samba
recovery of the four dead sons of a brahman
marriage of Anirudh with Usha after Krishna defeats Banasur
As you can see from the contents above, the events mentioned in the three scriptures are overlapping in many instances with the Mahabharat focusing on the Kuru clan and Harivamsa and Bhagvat Puran focusing on the Yadav clan and Shri Krishna with Bhagvatam giving a more comprehensive picture about him than the other two.