Hi @ManuelSissl
I understand the requirement you are trying to achieve.
But i would say here in this case why you are creating the simple products ?
Directly create configurable products and in that create a configurable options you can upload different image to those configurable options, you can also set a different price for each configurable product options. and each configurable product options consider as separate product.
As you are not selling those product as separately - so i would say this is recommended approach.
Correct me, if i understand something else.
Hope it helps !
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