Hi
You need somehow to expose Table 7505 (Item Attribute Value Mapping) to Power BI. Also, you need Table 7500 (Item Attribute) to build that relationship, (Item and ID are in 7505 and ID name is in 7500)
I could not find such a page. But maybe try to expose the following pages to see if you have any success or not
1) Page 7504 - Item Attribute Value List
2) Page 9110- Item Attributes Factbox