Other favourites include:
Prologue to Life/I Know You by slaymesoftly
Summary: Response to challenge #40 on the Bloodshedverse. Buffy gets sent back in time to meet Spike for the first time. Post Chosen/ Season 2
The Butterfly Effect by cousinjean
Summary: Five months after the events of "Chosen," a still grieving Buffy must follow a time-travelling demon back to 1997 (circa Season 2) Sunnydale to prevent him from destroying the timeline--and try not to destroy it herself in the process.
Then there's
Actions Past by DutchBuffy2305, which isn't post-Chosen but still fits the bill somewhat
Summary: Sunnydale, 1997. Buffy makes a wish, with consequences...Buffy from the past and Buffy from the future will have to square their destinies and their lovers.
And speaking of DutchBuffy2305,
Crossing into Unchipped Territory has a fantastic time travel element. Great interaction between post-Chosen Buffy and an AU S2 Spike
Summary: Buffy gets sucked into an alternate reality where she meets another Spike. Hijinks ensue.