E-residency has nothing to do with residency. Your comments don't really make sense here. It's a digital signature for managing Estonian companies, among other things. Being a Bahamas resident won't let you sign contracts on behalf of an Estonian company remotely.
In fact, you cannot be e-resident if you are resident in Estonia.
You can sign documents digitally without eresidency, just probably not qualified electronic signatures (QES), the highest 'trust level' of digital signature according to European standards.
Many businesses use docusign for instance.
Eresidency signature is not really used outside of Estonia anyway. Its mostly used in dealings with state authorities.
The eIDAS Regulation defines three levels of electronic signature: 'simple' electronic signature, advanced electronic signature and qualified electronic signature. The requirements of each level are built on the requirements of the level below it, such that a qualified electronic signature meets the most requirements and a 'simple' electronic signature the least.
'Simple' electronic signatures
An electronic signature is defined as "data in electronic form which is attached to or logically associated with other data in electronic form and which is used by the signatory to sign". Thus, something as simple as writing your name under an e-mail might constitute an electronic signature.
Advanced electronic signatures (AdES)
An advanced electronic signature is an electronic signature which is additionally:
uniquely linked to and capable of identifying the signatory;
created in a way that allows the signatory to retain control;
linked to the document in a way that any subsequent change of the data is detectable.
The most commonly used technology able to provide these requirements relies on the use of a public-key infrastructure (PKI), which involves the use of certificates and cryptographic keys.
Qualified electronic signatures (QES)
A qualified electronic signature is an advanced electronic signature which is additionally:
created by a qualified signature creation device (QSCD);
and is based on a qualified certificate for electronic signatures.