I'm pretty new with cryptocurrensies. But it makes sense to me that it needs online access. To resolve the seed, i'm guessing it needs access to the blockchain to create the wallet. How else would it translate the seed into a wallet?
No! Derivation of keys and addresses from the seed is deterministic and it does not require any extra data. It is definitely possible to create an Electrum wallet offline, as well as to restore a wallet from an existing seed. I did that several times.