You Do Need power plug adapter while traveling from Ireland (Eire) to Equatorial Guinea.

Here is Why You Need An Adapter

The outlet and plug type used in Equatorial Guinea are C and E and in Ireland (Eire) is G. This is how they look like.

Ireland (Eire)

In Ireland (Eire), outlets of type G are in use.

Type G

Equatorial Guinea

In Equatorial Guinea, outlets of type C and E are in use.

Type C

Type E