Saying 'when you grow up I'll marry you' to a child isn't harmless just because some people have heard similar jokes before. Adults, especially public officials, have a responsibility to set appropriate boundaries with children. The concern is about protecting kids and holding leaders to a higher standard not about pretending to be offended.
You mean Left Back / LWB right?
As you noted in their descriptions, both of these players are natural Left Backs! Targeting either of them as a Right Back option would mean playing them completely out of position. Besides, Chelsea already has Malo Gusto and Reece James holding down the right flank.