Expandable Table Visual

Here is how I would approach this. You'll need two tables, an index column, and two measures.

Table 1; Record Table

Table 2; Work Items Relationship Table

Note: it is important that the Project record's index value in Table 1 ranks lower (or higher) than the child record for the period you are reporting on.

1. Create a relationship between both tables such that 'Table 2[Child]' is One to Many 'Table 1[Work Items]'.

2. Create a hierarchy field in Table 2 with 'Table 2'[Parent]' and 'Table 2[Child]'

3. Create [Measure1] and [Measure2]. I added them to Table 1.

Measure1 = CALCULATE(
    MIN('Table 1'[Status]),
    'Table 1'[Index] = MIN('Table 1'[Index])
)

Measure2 = CALCULATE(
    MIN('Table 1'[Description]),
    'Table 1'[Index] = MIN('Table 1'[Index])
)

4. Add a matrix table visual to your report. Use the Hierarchy field you created in Table 2 as the Row Header and both [Measure1] and [Measure2] as the values.

You visual should now look like one of these sample matrix tables:

I think this is fairly straight forward, however, let me know if you would like me to expand on any of these concepts.

P.S. the index column can be replaced with another column such as a date or date/time column. But to keep this simple I used an index column to demonstrate how the Measures work.