Sorry if this was obvious to others, but having googled the fees for wise and revolut, I didn't pick up on some important details.
Wise has no membership cost, and seems to charge a fee of 0.6% for USD to GBP. It's hard to be sure about wise fees as I couldn't find anything published, except "from 0.39%" and this older post
https://wise.com/us/blog/fees-changing-usd-jan-18-gbpRevolut is free and paid "plus" version (£40/year).
The free allows for £1,000 per month with no fees, the plus allows for £3,000 per month with no fees. So if you were to use all the allowance, you'd have £36,000 for £40 fee, or 0.1%. That's not a huge savings, but works out to about £120/year cheaper than wise.
FX over the "no fee" allowance, Revolut is 1% fee for the free account, 0.5% for the plus account.
Note that Revolut chages a different rate at the weekend -
https://help.revolut.com/help/wealth/exchanging-money/how-much-does-it-cost-to-make-an-exchange/will-i-be-charged-for-exchanging-foreign-currencies/I hope this helps, and let me know if I've got anything wrong.