There are 11 Diglett to find on Honeycalm Island.
Honeycalm Island is the island towards the top of the Town Map. It has 6 islands tied to one central island with a tree on it. An easy way to get there is to fly to Tower of Waters in Challenge Beach. While facing away from the tower towards Challenge Beach head leftward on the water. Honeycalm Island is close by.
Alolan Diglett #1
Diglett #1 is on the tied island closest to the cliffs of the main island. It is hiding by some bushes near the Pokemon Den.
Alolan Diglett #2
On the same tied island as Diglett #1, Diglett #2 is hiding by the rock.
Alolan Diglett #3
On the second tied island (right of the one Diglett #1 and #2 were hiding on – when facing the tree), Diglett #3 can be found hiding in the sand on the shore.
Alolan Diglett #4, #5
On the third tied island (right of the one Diglett #3 was hiding on – when facing the tree), Diglett #4 and #5 can be found hiding in or near the sand on the shore. One is close to the central island whereas the other is closer towards the tip of the tied island.
Alolan Diglett #6
On the fourth tied island (right of the one Diglett #4 and #5 were hiding on – when facing the tree), Diglett #6 can be found hiding behind the bush near the Pokemon Den.
Alolan Diglett #7
On the fifth tied island (right of the one Diglett #6 was hiding on – when facing the tree), Diglett #7 can be found hiding in the flowers.
Alolan Diglett #8
On the sixth tied island (right of the one Diglett #7 was hiding on – when facing the tree), Diglett #8 can be found hiding in the flowers near the Pokemon Den.
Alolan Diglett #9, #10, #11
These three Diglett are all hiding in the flowers by the central tree. You may have to walk around the tree to view the flowers at a different angle in order to see the Diglett hidden within them.