If I cast Green-Flame Blade and use Divine Smite, does the smite apply to both creatures?

Green-Flame Blade uses the CAST A SPELL action, not the ATTACK action

Would you use strenght or intelligence modifier with a spell like Green-Flame Blade?

Bluelake district? What happened to Blacklake?

Would an arcane trickster using Green-Flame blade be able to benefit from sneak attack?