Coldwallet2020 is not connected to any of the coins/tokens blockchains we support. You generate a Public and Private key instantly. When you are ready to spend from your coins cold storage wallet, you will simply need to import the private key to a wallet that is online. Yes, retrieving coins from the Bitcoin core could take some time if the wallet is not syncs but using alternative like Electrum base programs or online with blockchain.com and for Ethereum coins/tokens myetherwallet.com or MetaMask will get your coins instantly. Other than Bitcoin and Ethereum, most Coin cores will take between 30 minutes to 3 hours to syncs (depending on your connection speed).