Is it misleading to claim lower emissions when we buy EACs but still use grid electricity?

It can feel that way, but it is not misleading if done transparently and in line with accepted standards.

When you buy electricity from the grid, it comes from a mix of sources. You cannot control where the electrons come from physically. But by purchasing EACs, you are claiming the environmental benefits of renewable electricity that has been added to the grid elsewhere. This is how the GHG Protocol defines market-based reporting.

It is important to explain this clearly in your reporting. You are not changing the physical electricity you use, but you are helping to shift demand toward renewables by matching your use with verified green generation. As long as the EACs are valid and properly retired, this approach is accepted and widely used.