ST Kaiburr Crystal & Any Possible Role In ST?

I'm wondering about the Kaiburr Crystal and if there might be any Possible role for it in ST. The reasons I wonder this is:

1) Originally Lucas had a plan for it to enhance/help/connect people use the force
2) Rouge One has it featured throughout the film in connection to an ancient Jedi Temple
3) These are what are used in a lightsaber.
4) Luke's lightsaber "calling to" Rey and the memories/visions connected to Luke.
5) We never got to see Luke's green lightsaber in anyone's hands during the present moments of TFA nor TLJ (just past flashbacks)
6) We never got to see Vader's red lightsaber - although I think I recall fans pointing out Luke might be wearing the crystal as a medallion or something now.

Any how I'm wondering where they may go with the crystal itself.

Will we see Luke's green lightsaber again? What will Rey see when she holds it? What flashbacks will it trigger to fill in any other missing history, if any?

Same question for the red lightsaber for Vader.

Did Kylo/Ben encounter this lightsaber in Luke's collection of relics and have a similar experience that Rey had in TFA, only he saw Anakin/Vader's past?

Could the Kaiburr Crystal be used as the means to connect force users to the past and future like a crystal ball is for a fortune teller, etc?

 

It's Kyber in canon. Luke did have a Kyber from an ancient sith warrior which a "jedi crusader" fashioned into a necklace as a trophy. It seems more like an easter egg than anything of significance at this point.
It's possible that it was the kyber crystal in the Skywalker lightsaber which called to Rey. We saw something similar happen when Ezra Bridger teamed up with Saw Gerrera in Rebels to track down the Death Star, only to be drawn to a giant sized kyber crystal which was undoubtedly on route to the battle station.

 

I do not think we will see much more about Kyber crystals again in this trilogy. Rey will have a complete lightsaber, by the time we see her again. Luke's Sith kyber crystal was also very cool indeed.