Versions:
MC 1.20.1
Forge 47.2.5
SFR: 20.1.3
AE2: 15.0.15

As you can see in this image below, while the upgrade does allow a SFR panel to connect to the ME system cable, it does not actually power the network whatsoever. It requires a physical energy acceptor to transfer (with or without the upgrade, doesn't matter), or placing the panel on top of specifically an ME Controller (with or without the upgrade).
Based on how the upgrade allows for the panel to connect to cables, i'm assuming this is unintended behavior/a bug.