It is possible for owners to sign transactions "on-chain". See: [Pre-Validated Signatures](https://docs.safe.global/advanced/smart-account-signatures#pre-validated-signatures), [`approveHash(bytes32)`](https://docs.safe.global/reference-smart-account/signatures/approveHash), and also known as "pre-approved hash" in the code.
It is possible for owners to sign transactions "on-chain". See: Pre-Validated Signatures,
approveHash(bytes32), and also known as "pre-approved hash" in the code.