McSwain graduated from Stephens College in 1974, before moving to Los Angeles.

McSwain's first job as voice director was for the English-language version of Lucky Luke.

[2][3] Among her most well-known animation productions are The Adventures of Jimmy Neutron: Boy Genius, My Little Pony, Bump in the Night, and Goof Troop.

In 2013, McSwain voice directed Transformers: Rescue Bots, Randy Cunningham: 9th Grade Ninja and Gravity Falls.

Since 2016, she is the voice director for the Netflix animated series Spirit Riding Free.