Want to apply Conditional formatting on matrix visual

Hi Manas0396 

Move your dynamic format string to a measure so you can re-use it:

Dynamic Format String = 
SWITCH (
    SELECTEDVALUE ( Sheet1[KPI] ),
    "No. of hero skus", "0",
    "Listing Share", "0" & """%""",
    "Availability (Hero SKU)", "0" & """%""",
    "Content Execution on PDP", "0" & """%""",
    "Rating And Reviews", "0" & """%""",
    "In search", "0" & """%""",
    "On category page", "0" & """%""",
    "Impression Share (only for specific formats).", "0" & """%""",
    "Revenue (EUR)", "#,.00k",
    "Spent (EUR)", "#,.00k",
    "ROAS", "0.00"
)

Create these measures:

Previous Month Total Value = 
CALCULATE (
    [Total Value],
    FILTER (
        ALL ( Sheet1[Date], Sheet1[Month_Year] ),
        VALUE ( Sheet1[Date] ) = VALUE ( MAX ( Sheet1[Date] ) ) - 1
    )
)
--NOTE: I had to use VALUE because [Date] as YYYYMM is not numeric

Variance = 
[Total Value] - [Previous Month Total Value]


Text Color = 
IF (
    CONTAINSSTRING ( [Dynamic Format String], "%" ),
    IF ( [Variance] > 0, "green", "red" )
)

Your current setup isn't the best practice. If it were me I'd use a dedicated dates and create a real date column in the fact table.