Power BI Dynamic Column Selection based on Secondary Table filter

Hi,

According to your description, i think you can not generate table dynamically by selecting slicer, but i have a workaround:

Please take following steps:

1)Add an index column to Table 1 in Query Editor.

2)Try this measure:

Measure = 
SWITCH (
    SELECTEDVALUE ( 'Table 2'[Dimension Select ] ),
    "Sector", MAX ( 'Table 1'[Sector] ),
    "Region", MAX ( 'Table 1'[Region] ),
    "Employee Competency", MAX ( 'Table 1'[Employee Competency] )
)

3)Choose [Index] from table 1, [Dimension Select ] from table 2 and this measure as a matrix visual:

4)Turn off 'Word Wrap' in Format/Column headers and Format/Row headers:

5)When you select one value in slicer, it shows:

Here is my test pbix file:

pbix 

Hope this helps.

Best Regards,

Giotto Zhi