I like it. Not really discoverable, so you might need an extra icon somewhere. Reminds me of the iOS calculator where you can swipe left to remove characters from the input. Totally not discoverable, but very useful and intuitive once you know it.
Sats / btc / fiat units change in invoice creation - how do you like this solution? https://nostr.build/av/b48d8864f25a05cf0bc439a0f0d131f9b4de26bf81b8a7e711ac08a55bd87a72.mov
Discussion
Yes that is my main concern, however I assume most people will discover it when they will click on the input to change the value and see the hover state of the unit whole doing that. But perhaps the safest is to add an icon as well