You probably would not be able to earn interest on LTC on decentralized platform (same with BTC but you can switch it to WBTC). And most of their staking options that offer insane outcome are provided only for shitcoins and it is a huge doubt if it worth investing on these alts at all. The best thing you can do is stick to anything reliable like ETH there.
I like exodus wallet with built in staking/rewards. Not sure about decentralized exchanges or staking platforms though.
I guess they are providing staking on blockchain, not on DEX.