All the wallets below can store your BitcoinSOV (BSOV) safely. They all support custom ERC20-tokens. Usually you are required to add BSOV as a custom ERC20 token.
The contract address for BSOV is: 0x26946adA5eCb57f3A1F91605050Ce45c482C9Eb1
Use the popular and trusted online wallet. You do not have to download anything to use this wallet.
The safest way to store your cryptocurrency is by using a hardware wallet. You can store your BitcoinSOV (BSOV) just like all ERC20 tokens on Ethereum.