Oiled, greased or waxed leather is robust smooth leather or nubuck leather, to which a greasy - oily - "waxy finish" is applied. Often these waxes, oils or fats are also dyed and therefore such leathers have a slight risk of dye transfer. Such leather is labelled as oiled leather, waxed leather, pull-up leather, saddle leather or as vintage leather.
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Oiled, greased or waxed leather is mostly offered as bag, belt, shoe or as furniture leather.
https://www.leather-dictionary.com/index.php/Pull_up_leather...


Finishing determines the appearance of the final surface of the leather and the surface properties. This includes colouring, waterproofing, **wax dressings**, but also mechanical processing stages such as ironing or embossing of the leather.
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There are also leathers which have an oil coating or **wax coating**. For these leathers, uncoloured or dyed waxes and/or oils are applied to the leather surface. Such leather is called pull-up leather.
https://www.leather-dictionary.com/index.php/Finish

https://www.leather-dictionary.com/index.php/Oils_&_fats_in_...

wax dressings e wax coating riportano entrambe alla pagina del primo link
sopra

"finitura a cera incorporata" è un'espressione che non ha alcun riscontro, non ne ho mai sentito parlare
potresti chiedere al cliente che cosa intende, ma per me è sufficiente quanto proposto