Some exchanges allow the setting up of automatic DCAing.  You can choose an amount and a frequency, perhaps daily, weekly or some other inverval - exchanges will vary in t how an automated DCA could be set up and part of the reason that I don't like them is that they usually cannot be set up for a very specific time, but instead at the the most daily, so the exchange will likely batch all of the DCA's at the same time and might even play shenanigans with the DCAs, though maybe some of the exchanges have improved their systems.  If you are going to use an exchange to automatically DCA, I would look into how they describe their way of executing the automatic DCAs.

Manual DCA is that you do your own buy, and surely you can even set your buy up as a market taker limited order rather than having your order be a market maker.  Market takers have lower fees than market makers, and of course, people are going to have differing rates and differing options depending on their geographical location and which exchanges are available to them.

Regarding your statement:  "it really picks my interest."   I am pretty sure you meant to say:  "it really piques my interest