If you don't know the discworld books by Pratchett, Granny Weatherwax it the most formidable character. She is a witch, but doesn't generally use magic to solve problems; preferring to use persuasion and manipulation. In saying that her magic is extremely powerful.
Maybe a bard with huge wisdom, persuasion and intimidation.
Yeah, I agree with druid as the base. She did a shapeshifting duel with one of the archchancellors, as well as her borrowing, and that's the class that uses it the best.
But don't forget that she was a hedge doctor and midwife as well. She'll want healing proficiency. She'd have some kind of bonus for perception with humans imo, even if it was DM fiat rather than a class skill.
But she's definitely multi class since she pulls off a huge time manipulation ritual, can planar travel (at least if you count her going into the realm of death to retrieve Tiffany Aching as planar travel), and similar feats that would normally be non druid types of spells.
"So," Nobby said, as he sidled up to the Librarian, "do you have any lady friends?"
"Ook." the Librarian replied.
"I don't think he's talking about the cook," a voice spoke from about twelve inches above the ground. "I think he means someone more personally important," the voice snickered.
"Ook?"
"Yeah, you know, someone to share the bananas of life with. A comfort in troubled times." Nobby stared wistfully into the middle-distance.
The Librarian gave a complicated multi-jointed shrug, as if to say in one gesture, "Why would I ever want to share bananas?"
As if called by a psychic connection, the pitter-patter of hundreds of feet could be heard as the Luggage trundled up beside the Librarian. The lid opened to reveal dozens of bananas in varying states of ripeness
"Ook!" the Librarian exclaimed, patting the Luggage amicably on the lid
"True enough," said the voice near the ground, accompanied by furious scratching. "I could go for a sausage myself. Or even something from Dibbler." A tail wagged hopefully in the direction of the Luggage.