Liquidity pools native to the chain
The only pool that could be done native to the chain at this point is HIVE-HBD, since every other token is on some layer 2. I think @abit once mentioned the possibility of adding it.
That being said I think most would probably suggest to wait for a smart contract platform and do it there instead of native.
Yes, just hbd/hive.
A non third party solution.
I'm running the dswap bot for hive-engine and wanted the same functionality in the hive wallet.
I'm not well versed enough to know the difference between what that does on a third party server and doing it in the hive nodes instead.
If it 'slows down the chain' then it wouldn't be a good idea, at this point.