For a trip to Europe in Fall, I'd generally bring 3 pairs of shoes:
-Pair of sneakers
-Booties/Boots/knee-high boots
-Loafers
Yes! While Europeans dress more formally than Americans, they do wear blue jeans. Just make sure your jeans are in good shape and without ornamentation.
Generally, I'd suggest a light jacket, and preferably one that's waterproof.
Base layers, like a long-sleeved t-shirt or light sweaters in lightweight merino wool, are the name of the game.
I generally opt for a small,
cross-body bag in neutral leather for European travel, regardless of the season.
Beyond the much-discussed purse, you'll also want a few other accessories for Europe in the Fall:
-Sunglasses
-Umbrella
-Scarf
-Socks