When Catherine trades in her virginity to get pregnant, the skin of her mate's back and legs is tanned, while his buttocks are perfectly white. There were neither sunbathing nor a pair of trunks in 18th century.
When Catherine borrows the wooden cross from Potemkin, it is hanging from a simple string. But when she gives it back, it has been strung with matching wooden beads. There is no explanation if this is a different prop or if Catherine added the beads herself.