The Elementalist archetype allows Sorcerers with Elemental bloodline to replace their Advanced Bloodline focus spell with Repel Metal or Wood Walk, which are both 4th-rank Domain spells. The other options, for replacing Fire, Air, Water, and Earth, are 3rd-rank Druid Order spells.
I imagine this isn't intentional, because all Bloodline spells are 3rd-rank, gained at 6th level, and a Sorcerer wouldn't even be able to cast 4th-rank focus spells for another level.
"You can't cast a focus spell if its minimum rank is greater than half your level rounded up, even if you somehow gain access to it." -Player Core 298