Is there a big difference in charging between the Sport 1 and 2 ?
Not unless the Level 2 car has the optional 19.2kW charger, which would allow faster level 2 charging if your charging station can support it.
The 19.2kW charger can also support V2H capabilities but you need even more equipment from GM to do this, and this anecdotally seems to be pretty rare in the wild but some people like the idea this could be possible later.
I skipped the 19.2kW charger.
For DC fast charging, all Lyriqs have a max 190kW rate if all conditions are met (usually not the case).