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

Here is Why You Need An Adapter

The outlet and plug type used in Ireland (Eire) is G and in Nicaragua are A and B. This is how they look like.

Nicaragua

In Nicaragua, outlets of type A and B are in use.

Type A

Type B

Ireland (Eire)

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

Type G