Only Connect Wall #2

Using S10 E17 as an example, our groups are:

Teal, Merganser, Eider, Wigeon (types of duck)

Flying Scotsman, Rocket, Puffing Billy, Mallard (famous trains)

Orient Express, Mesopotamia, Styles, The Nile (Poirot locations)

Malik, Tomlinson, Horan, Payne (1D members)

Sorting the items alphabetically, we get:

Eider, Merganser, Teal, Wigeon

Flying Scotsman, Mallard, Puffing Billy, Rocket

Mesopotamia, Orient Express, Styles, The Nile

Horan, Malik, Payne, Tomlinson

We should therefore input the groups as follows:

Eider, etc.

Flying Scotsman, etc.

Horan, etc.

Mesopotamia, etc.