No. Currently, it is not possible to directly edit the cost basis of a transaction. Editing a transaction or changing its historical price (which is not related to cost basis) will not update your cost basis and is not recommended.
Instead, to update your cost basis, we recommend following this troubleshooting workflow:
Step 1: Import your missing transaction history data - be sure to import all the exchanges, blockchains and wallets you have used to buy, sell and swap crypto over the years
Step 2: Follow along with the step-by-step instructions on the MCB Troubleshooting Tab
In most cases, importing your missing transaction history data (including all wallets and exchanges you have used and all years of your trading history) and reconciling your data by following the steps on the MCB Troubleshooting Tab are the best ways to resolve your missing cost basis warnings.
That said, if you have followed all of these steps but are still unable to resolve your missing cost basis, CoinLedger does allow you to manually enter your cost basis by creating a Manual Position. You can enter a Manual Position for any asset that is missing its cost basis on the Transactions page. Learn more about this process here.