Home Depot or Walmart has a battery oprated fan, it'll run off DD batteries or electric current.
I keep rechargeables & regular batteries.
That might help in camping situations.
If you got to travel with wet booties, get a bunch of those USPS flat mailers.
They're made of Tyvek, they're waterproof.
I use them all the time for wet booties & bathing suits.
GL & HH
I've been using the PEET boot dryer for years. Works great.
https://smile.amazon.com/gp/product/B001J4HQ76/?tag=treasurenet01-20