I have just tried it and it didn't work. I do leave spaces between the seed words don't I?
Did it even create the same addresses as from Electrum? If so, are you sure that this BTC wallet even had coins in it at the time of the BCH fork?
Did you put the BTC address into blockchair.com and see what it says?
For instance, here is an old coinbase address from Block#200 that is still 'unspent': 1HwmP33SaknLYShXfjVU8KmVThU3JiuVgH
If we put that into the search at blockchair.com we can see that
it has BTC, BCH and BSV:
As a test, try and see if you can replicate this scenario with "known good" data. I just created a test BIP39 seed:
margin mountain ripple maid situate weasel measure various network solution manual sustain
I loaded it up in both Electrum 4.1.5 and Electron Cash 4.2.5... I used "BIP39 seed" option in when entering the seed on both. In Electrum, I chose "Legacy" - m/44'/0'/0'.... and in Electron Cash, also opted for the legacy m/44'/0'/0' option... They both generate the same addresses:
NOTE: in Electron Cash, you have to click this icon in the bottom right corner to swap between cashaddr and Legacy address formats:
See if you can create the 2 wallets in Electrum and Electron Cash and see if you also get the same addresses generated as the first 2 addresses in the address list:
- 1ArEK4rsCkvUh2Q4ZVa6xXQLnBy4yQtwPy
and
- 1GEZkp7FWEURQm88Dyt2VSRSbnuuCYKov8
If that works, but you still can't get it working when using your blockchain.com 12 word seed, then I suspect the wallet you're trying to get the BCH out of, is NOT part of your Blockchain.com HD wallet... so it won't be generated by the 12 word seed.
It might be an
imported private key/address in blockchain.com wallet instead.