Were there only seven Saptrishis? Were there any females amongst Saptrishis? Are they ever mentioned as doing parikrama around Sun or Earth? Have there been multiple sets of Saptrishis during various ages? During which Yuga did Saptrishis live?
There are multiple questions!
According to the Satapatha Brahmana, the Seven Rishis are
गौतम, भरद्वाज, विश्वामित्र, जमदग्नि, वसिष्ठ, कश्यप and अत्रि; Gautama, VaradvAja, VisvAmitra, Jamadagni, Vashishtha, Kashyapa and Atri.
According to the Mahabharata, the names are
मरीचि, अत्रि, अङ्गिरस्, पुलह, क्रतु, पुलस्त्य and वसिष्ठ; Marichi, Atri, Angiras, Pulaha, Kratu and Vashistha.
Manu adds three more names to these sevens and calls them 'PrajApati' or the progenitors of Mankind.So they must have belonged to the Satya-yuga (and seems immortal.)
There are NO females in them.
The are here not perceived as the stars and so the question of moving around the Sun or the Earth does NOT arise. There are seven stars called together as the Saptarshi-mandala though:
In astronomy the seven Ṛiṣis form the constellation of "the Great Bear"