The 2 approaches present a number of differences.
Funds custody:
By staking your tokens on the platform, Meria ensures the custody of your funds.
By delegating your tokens directly from your own portfolio, you are still in control of and responsible for your funds.
Fees:
Fees apply when staking your tokens on the platform.
NB: Meria does not charge any fees on deposits. Only on interest.
By delegating your tokens directly from your own wallet, transaction fees are at your expense, while interest charges may be lower.