brainflayer is used only to quickly search one set of strings into another set of strings.
You make bloom filter for him and search for strings.
But there isn't going any conversion!
If you search for passwords or brainwallets - this won't work!
Passwords/brainwallets are not converted while searching.
Brainflayer is just a simple bloom filter.
It does find matches, but there is no conversion of anything.
Brainwallets from -i file are not converted in any way!
There are many manuals on the Internet saying:
https://www.forknerds.com/brainflayer-crack-bitcoin-and-ethereum-private-keys/
Quote
After the bloom filter creation, everything is ready for brute-forcing. Grab your longest wordlist and attack! The following commands are the most common ones:
$brainflayer -v -b btc.blf -i wordlist.txt
$brainflayer -v -b btc.blf -i wordlist.txt
This won't work if we have brainwallets in wordlist file and bloom filter with addresses. It can work only if in wordlist there is ADDRESS which will be in btc.blf!