Download the blockchain

Hi,
i have buy a Pi 4 and i will receive it in 1 week. But i want to download the blockchain before i receive the Pi4, and transfer it on Umbrel after i install it on the Pi 4. Is it possible ? If yes how can i download the blockchain and after transfer it in Umbrel ?

I have about the same question : I have already the blockchain synced on a Windows PC. Can I configure Umbrel to get the blockchain (via high speed LAN) from my other LAN PC ?