Which iSCSI initiator type can be used with any network interface card?

The software iSCSI initiator is implemented as a VMkernel module that handles all iSCSI and TCP/IP processing in software, so it can operate over any generic standard NIC without requiring TCP Offload Engine (TOE) or iSCSI-specific hardware capabilities.

Software FCoE is a Fibre Channel over Ethernet protocol - not iSCSI - and it still requires a converged network adapter (CNA) that supports FCoE offload, so it is not usable with any arbitrary NIC.

A hardware-independent iSCSI initiator (also called dependent hardware iSCSI) requires a NIC with TCP Offload Engine capabilities and cannot operate on a standard NIC without those offload features.

A hardware-dependent iSCSI initiator requires a dedicated iSCSI HBA that processes all iSCSI and TCP/IP logic in hardware, making it specific to that hardware platform.