Calculation based on 2 or more variables (slicer/parameter?)

Harom Hey,
try below things

1st table

CurrencySelection =
DATATABLE("Currency", STRING, {
{"USD"},
{"EUR"},
{"GBP"}
})

2nd table 

PeriodSelection =
DATATABLE("Period", STRING, {
{"MTD"},
{"YTD"},
{"QTD"},
{"Full Year"},
{"PY MTD"},
{"PY YTD"}
})

once you have above 2 disconnected (Newly created table) then you have create below measure

SelectedSales =
VAR SelectedCurrency = SELECTEDVALUE(CurrencySelection[Currency])
VAR SelectedPeriod = SELECTEDVALUE(PeriodSelection[Period])

-- Step 1: Apply currency conversion logic (example rate logic)
VAR SalesInCurrency =
SWITCH(
SelectedCurrency,
"USD", [Sales_USD],
"EUR", [Sales_EUR],
"GBP", [Sales_GBP],
[Sales_USD] -- default
)

-- Step 2: we have to write a period logic now
RETURN
SWITCH(
SelectedPeriod,
"MTD", CALCULATE(SalesInCurrency, DATESMTD(DateTable[Date])),
"YTD", CALCULATE(SalesInCurrency, DATESYTD(DateTable[Date])),
"QTD", CALCULATE(SalesInCurrency, DATESQTD(DateTable[Date])),
"Full Year", CALCULATE(SalesInCurrency, YEAR(DateTable[Date]) = YEAR(TODAY())),
"PY MTD", CALCULATE(SalesInCurrency, DATESMTD(SAMEPERIODLASTYEAR(DateTable[Date]))),
"PY YTD", CALCULATE(SalesInCurrency, DATESYTD(SAMEPERIODLASTYEAR(DateTable[Date]))),
SalesInCurrency -- default 
)

above solution is fully scaleble for future.

Thanks
Harish M
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