New / adding "legacy" activity

I started dabbling in Crypto with Robinhood and have since moved completely off that platform. All I did on that platform was buy/sell DOGE. I would like to add a transaction that summarizes all of my RH into one entry so that it shows on my dashboard as part of my lifetime profit.

Using fictional examples: Over the time I used RH, I bought a total of 2,000,000 DOGE for a total $10,000. I sold all of it for $10,500. I’ve tried all sorts of things to get it to show up correctly.

FWIW, all of my RH activity was in 2020. All of my non-RH crypto activity has been 2021. I don’t mind using dates like 12/30/2020 for a “purchase” and 12/31/2020 as a “sell” that reflects my aggregate totals.

When I try to do this, I wind up with numbers that dramatically inflate my deposits on the dashboard graph. I love the dashboard as is because it imported from my Coinbase and Binance wallets perfectly. The deposits are correct and the percentages are exactly what I’m looking for.

I don’t need to get the actual purchase/sell amounts in there. I’m fine with a single “Other transaction” that shows $500 profit prior to getting into Coinbase/Binance.

Hope this makes sense. Any help is appreciated.