Sadly I didn’t take screenshots. I was using an old iPad with up to date software.
From memory, I hit the transact button at the bottom of the Brave wallet window, selected 100% of the available Eth in optimism, selected send via optimism, and as prompted scanned the QR that Binance gave for Eth via Optimism. That’s when the Red error message appeared.
Excuse my phrasing if it doesn’t make sense, I don’t understand the mechanisms.