Opening dppspecies.db or dppmovesets.db isn't the way to go for modifying movesets or existing pokemon, and there aren't any really convenient means to do that anyway. However, ShoddyBattle has a feature called mod list for editing the movesets and abilities of existing pokemon.
The server.properties file that's used to modify the properties of the server has the following field:
#Patch file to apply against the metagame
server.patch =
By default the program uses no patch, and the metagame is thus the normal one. However, you can define a patch file by adding it's filename after the '=' - mark and by placing the file to the same folder with the server.properties -file. Then you can modify existing pokemon by adding lines to the file you defined as the patch like this:
Slugma: a-Flame Body, a+Blaze, HP: 80, atk: 80, def:100, satk: 80, sdef: 80, spd: 5, Surf, -Flamethrower;
The pokemon's name is at the beginning (Slugma:). Then you add whatever modifications you want. For example the previous line removes it's ability Flame Body (a-Flame Body), gives it the ability Blaze (a+Blaze), changes it's base stats to the ones defined up there, gives it the new move Surf, and removes it's already known move Flamethrower from it's movepool. Do note the ";" in the end and the ","s in between commands, as they're required. Also, remember case sensitivity.
Adding new pokemon can also be done through the mod list by adding a line like the following to the mod list:
Add Pokemon: Missigno, 80, 80, 80, 80, 80, 80, Water, Flying, None;
Therefore the pokemon's name is Missigno, base stats are all 80 (the order is Hp, Attack, Defense, Speed, Special attack and Special defense), type is Water/Flying (for monotyped pokemon put None to the second spot), and the pokemon is genderless (the gender options are Both - both genders available, Male - male only, Female - female only and None - genderless). And next you just give it the movepool and abilities with a line similar to my Slugma example. For example:
Missigno: a+Levitate, Water gun, Sky attack;
That gives it the ability levitate and a movepool of Water Gun and Sky Attack.
However, do note that unless something that I don't know about has been added to the ShoddyBattle sources that allows a server to serve sprites, without programming a sprite updater and running it or adding the sprites to your computer manually (just run a search on your computer for "ffinneon" and you should probably find them) the sprite displayed on new pokemon in battles will be the standard Missigno sprite.
Seeing as it's been some time since the last time I've used modifications like this, if anyone notices a mistake or something important left out in my post, please correct it.