Variants in DE / EN Shop 1 Inventory

We have 1 product that is sold as a set, this once as GERMAN and once as ENGLISH created, each with the variant COLOR (red, blue, green) and CONTENT (5ml, 10ml). So, for example, the red product has a 5ml and a 10ml bottle and this as an English and once as a German product. The stock management is active on the variants!
If I now sell a German product in red color and 10ml, currently only the German product, red variant, is reduced by -1 in stock management.
But, we want that from the maximum for DE and EN available pot (10 pieces)
the -1 will be deducted. So, that the system understands that it doesn’t matter if EN or DE was bought and it deducts the value from the main sum, no matter if it buys from DE or EN.
Is that possible???

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