An update: I used Wise today to transfer the equivalent of 200 Euros (in USD) to my friend in Italy as a deposit on a fall vacation rental in Florence. My friend also has a Wise account. It could not have been easier, faster, or cheaper.

First, I opened a Wise account online. Took a couple of minutes. To make the transfer, I entered my friend's email address, and it asked if [name] was the right person. I confirmed. I could then have deducted the funds from my bank account, a credit card, funds already on deposit in my Wise account, or one or two other options. I followed the instructions to connect Wise to my bank account. (I can disconnect it later, if I wish).

I then entered that I wanted my friend to receive 200 Euros and that my account was in USD. It told me the (entirely fair) exchange rate, the (small) fee to make the transfer, and the total amount in USD to be deducted from my account. I pressed OK, and that was that. Transfer completed.

Amazing.