Linked clones do not exist in ESXi. Horizon Composer is what is/was used to create them, and that requires a vCenter Server and a bit of infrastructure, including a database.
No, you can create them if you only have vCenter via its API. No extra infrastructure beyond that, though. The pyVmomi library has example code of how to do it. IIRC it is true that standalone ESXi does not offer the option to create a linked clone by itself, but if I wanted to be a pendant I'd argue that linked clones do exist in ESXi, as that is where vCenter deploys them.