Foreign Currency Holding for CGT calculations

Would it be possible to add a foreign currency wallet/holding (e.g. USD) and per broker (or per Stock/ETF holding) have a setting so that each "buy" consumes USD from this wallet/holding and a "sell" adds USD to this holding. Also, dividends are paid into this wallet/holding. This way, the Capltai Gains/Losses can be calculated on the currency holding. I think the only way to mimick this at the moment is to create a custom USD holding and manually enter a buy and sell for each trade and dividend distribution, along with any other fees charged in USD.