Blocknet have a very different approach in execution. Last I checked you had to download all the blockchains for any assets you wanted to trade on their Multicurrency wallet, this is not the case with Stakenet as their MN network hold all the various blockchains so you don't need to. This keeps the wallet clients very lightweight and fast, also means it can be ported to any device like mobile for example.
Also don't Blocknet use Atomic Swaps? If so then XSN's Lightning Swaps are superior as they are offchain over Lightning Network it means they are instant, can be done for little to no fee and theoretically infinitely scalable.
Full node trading maximizes security and eliminates risk as you are confirming utxos, raw transactions, etc involved in trades directly on your own fully synced node.
>Multicurrency Wallet
Where is this wallet? I can't find it anywhere. Regardless of such this is already capable on Blocknet - there is a group right now utilizing its XRouter technology that have built a working prototype which will be finished soon. However, anyone is free to make their own - the Service Nodes on the network are running full nodes of blockchains and provide access to all the necessary calls needed in order to create a lite client. As I hinted at before this is nothing unique for XSN.
>Atomic Swaps
Yes Blocknet utilizes Atomic Swaps and has a current working product you can download and use:
https://blocknet.co/#downloads I can't seem to find XSN's DX... is it working yet?
>Lightning Swaps
If correctly written, these are also atomic swaps. The difference here is one is on the LN and the other isn't. Lightning is all based on channels. "Superior" is highly subjective - there are many limitations and added risks when dealing with channels because within the channel the activity isn't recorded to the chain... only once the channel is closed does a transaction post to the respective chain. The way the channels are interconnected also poses issues for traders which can rack up fees considerably as your transactions tries to find the best route, so they're definitely not always cheap or fee-less! Channels can also become centralized based on how the network is currently designed, which makes them targets for foul play. I'm not saying it's bad to support LN - it's actually good practice to support as many features as possible, but in lightning's case users should be aware of the risks involved as its security guarantee as far as trading is concerned can't be compared to a pure CLTV swap that records to the respective chains during and after the exchange.