Our requirement : To create one material code (eg., A123) with different material type (HALB & UNBW) in two different company's plants.  We have created A123 material code with HALB in 1000 company's 1100 plant. While creating A123 material with UNBW material type in 2000 company's 2100 plant, system is taking default material type as HALB, as already created for 1000 company's 1100 plant. 
This requirement is due to the Job work process (non-valuated material) in 2000 company. 

The basic data (like Matl. no., description, UOM etc.) in material master are maintain at client level. We can not maintain the same at company code level. So in your case you have to maintain two seperate code for different companies, with different matl type. 

But you can for the same material type to define, that in some valuation areas it has update by value and quantity, but in another valuation areas only by quantity. Maybe you don't have to have two material types:)

Detail and what are the settings are required in customization:

tr.code OMS2 
1)Select details of material type and on end of screen in part 'Quantity/Value update" select for Value update radiobutton "By Valuation Area" 

2)After that on left side of screen select folder "Quantity/Value update" and set in which areas you need value update by setting indicator in column "Value update".

Fast links:
Which Price control should be used for Different Material Type?
Price Control V or S in material type

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