You Do Need power plug adapter while traveling from Malta to Jordan.

Here is Why You Need An Adapter

The outlet and plug type used in Jordan are C, D, F, G and J and in Malta is G. This is how they look like.

Malta

In Malta, outlets of type G are in use.

Type G

Jordan

In Jordan, outlets of type C, D, F, G and J are in use.

Type C

Type D

Type F

Type G

Type J