I only know of opposite spinning beys having slow motion burst results for when a faster spinning bey bursts when hitting a slower spinning bey, can this happen with same spinning beys?

I only know of opposite spinning beys having slow motion burst results for when a faster spinning bey bursts when hitting a slower spinning bey, can this happen with same spinning beys?

Yes.

Yes but typicall only if there have been many hard hits earlier in the battle. Basically think an Attack type vs Defense/Stamina Type. Towards the end of the battle, Attack TYpe is running out of stamina but the Defense/Stamina Type is just one touch away from Bursting.