I'm using QGIS 3.10.

I'm trying to label my map with values taken from a different layer (meaning not my atlas coverage layer), which is intersecting the atlas cover layer.

This layer named "Colorisé" has a categorized style using the field "color\_id". I want my legend items to be labelled with the field "idprop".

I have tried using this expression (1), which returns the featured items not individually but as a list :

```
aggregate('Colorisé', 'concatenate_unique', "idprop", intersects($geometry,@atlas_geometry), ',', "idprop")

```

And I have tried using the expression below (2), which returns the first value it can find (I guess) and applies it to all my legend items :

```
attribute(get_feature('Colorisé', 'color_id', intersects($geometry, @atlas_geometry)), 'idprop')

```

Can you guys tell me if I'm anywhere close to getting the desired results ?

You can find below an excerpt from the table of attributes of the layer "Colorisé" and an image summing up the situation.

[![enter image description here](https://i.stack.imgur.com/AHsxu.jpg)](https://i.stack.imgur.com/AHsxu.jpg)

[![enter image description here](https://i.stack.imgur.com/Q9Koe.jpg)](https://i.stack.imgur.com/Q9Koe.jpg)

**EDIT**

Using this expression seems to be working in the preview, but the labels end up being empty :

```
attribute(get_feature(@layer,'color_id', 
attribute($currentfeature, 'color_id')),'idprop')

```