Match Value In One Row To That In Another Row That Shares Common ID

I am looking at some combination of Index, Match and array functions in order to assign a value, in this case a currency, based upon an instance where another data item with the same trade ID already has that currency assigned to it.

Basically I have a list of data where there are a list of trade IDs for each data row/item.
In some cases there will be two rows of data that have a common trade ID.

For example there may be two results that share a trade ID eg 450222, one in EUR, one in another currency eg GBP.

What I need to do is create a formula in other column to the right of my data that recognises that if a trade ID is assigned to a non-Euro currency then to apply the foreign currency to both trades with the common ID.

ie change

Ref 450222 Ccy EUR
Ref 450222 Ccy GBP
Ref 450223 Ccy USD
Ref 450223 Ccy Eur

to

Ref 450222 Ccy GBP
Ref 450222 Ccy GBP
Ref 450223 Ccy USD
Ref 450223 Ccy USD

An offset function can't really be applied as the order of the data is random. My subsequent calculations involve a SUMIFS on GBP, USD etc.