question

You can activate Pull on Input Pane. A combiner need at least 2 input port connections. They can be from the same queue ahead of the combiner.

You need a logic that allows every item type to enter through input port number 1. And any item Type entering the combiner by input port number greater than 1 must be equal to the item already present from input port number 1

current.first.labels["Type"].value == item.Type

This is a logical test statement to compare first already received item Type label and any other item being able to enter next.

An tested item will be pulled if the return value is true by a value 1 or greater than 1. A tested item is rejected if the return value is 0 or seen as logical false.

You can write the logical test statement directly in a return line for any port greater than 1 condition.

Pull Requirement

default header

Object current = ownerobject(c);
Object item = param(1);
int port =  param(2);

added source code

if (port == 1) return 1; // first item pull everything
if (port > 1) return item.Type == current.first.labels["Type"].value; // further items

You need to add any picklist option and click on the source code editor icon looking like a parchment roll. Edit the code to distinguish between first any following item entering the combiner.