It's one of the most original ideas for visual novel game i've seen in my life.
The idea of two people from different nations falling in love isn't new. But your ant/yuri version is great. Making citizens of two colonies look and exist in very different way is good idea too.
I like the artstyle. It's a bit simple but still good looking. Well done sprites. Also you did great job with "animating sprites" - different face expressions, positions of hands, "simulating movemont" etc.
The story of two woman befriending each other and getting attached to each other was very sweet. They were spending time learning interesting facts about their works, nations, colonies and... about each other. And they enjoy spending time together.
They had crazy idea... and it got them in trouble... But the justice and frienship won!
And they had opportunity to visit their colonies :) Their colonies stared helping each other.
Val and Char menaged to create special bound. The love
They had a few problems but the both nations accepted their relationship after some time. Happy ending :D