Homeplug is a defunct standard that had some real limitations, Ethernet over Power is a generic term relates to any standard of network over power lines.

The G.hn powerline standard is a massive improvement (despite being almost as old and is closer to MoCA as it will actually work over coax and other copper wiring, not just power lines) for both performance and stability, but the Homeplug standards have probably ruined the public perception.

G.hn is also a bit weird because the Wikipedia page presents it as how carriers could use, not as a home network option, even though a few home pieces of equipment are available, such as the TP-Link Deco PX50 which uses G.hn for the wifi backhaul.