The <Sparks of War> Galactic Seasons objective is a high value, group oriented objective that usually involves a decent chunk of time to set up and find the people for. Being worth +12 Season Points and +15 GAME Currency makes it all the more worthwhile to attempt. However not everyone has the time or resources to get an organised group together to kill 25 Champion Mobs across various planets.

However as an Imperial Player, there is a group of tough but Soloable, Champion quality Republic Droids that you can kill Solo on Ilum with a companion, or even in a small group. Much easier then forming an Operations sized group and warring on a planet like Yavin for 25 kills.
While you can also do this as a Republic player against the Imperial Spaceport NPCs on Ilum as well, the Republic enemies have slightly less HP and damage output, making this objective a little easier if played by an Imperial.

To find the Republic Spaceport, head to the coordinates X: 500, Y: 560, aka the snowy rooftop covered in Igloos directly above the Republic Spaceport base. There is a respawn point a few hundred meters north if you die.
On the rooftop of this base the Republic Drois are easier to kill then other planets, and are spread out much more thinly, usually being in groups of up to 3 enemies instead of 5-10 or more near the bases physical entrances. The turrets at either end of the base work as well.

The same can be found for the Imperial Base at X: 350, Y: -430, however like I suggested earlier, the Republic base has slightly easier enemies making playing as an Imperial to Solo this Season Objective preferential if you value your time.

Alternatively for weeks where Ilum isn’t available, you can kill the lone Guardsmen duo outside of the Republic Base in the Dune Sea on Tatooine as an Imperial player.