Hello
so basically i have 3 wallets back from 2014 created on blockchain.info ( now .com ).
I got the 12-mnemoric Seed phrase.
My question now is, can i import the related wallet with that 12-word on for example a hardware wallet?
And how can the Bitcoin-Network even recognize what adresses etc are behind thos 12 words if its created on a completely different plattform?
The software you made use of is just like a generator that creates a seed phrase from a given set of word lists and then hashes it to give you your public keys --> addresses and your private keys separately. The hard ware wallet will recognise the seed as a valid check sum as long as it is a supported format which most likely could be BIP39.
Also last but not least, as far as i can remember blockchain had wallets with private keys back then, meaning in case if i restore the wallet which contained a legacy adress it will be also restored?
It doesn't actually matter the number of addresses or the type of address you had , as long as it was generated under that seed , once you sync with the network via a wallet software with that seed phrase you get access to all the addresses.