Hey, i cant actually rate your team because i have no time, but i have something to say anyway. Firstly, while i understand the bulk you get with eviolite on chansey you should really run blissey instead of chansey here, the sp atk of chansey is really underwhelming while blissey can actually do something.
Second, i think you should really try sleep powder over something else on Jumpluff, probably giga drain since hp fire is needed to catch grass types, sleep powder will allow you to start your annoying strategy, without it i doubt you will have many chance to sub seed teams. Also, while i understand you like jumpluff, venusaur is somehow better, its not weak to stealth rock, and it can absorb toxic spikes, and it can have the same set but with a better bulk and typing. A spread of 252 hp / 240 Def / 16 speed is what i used on venusaur on my team, give it a try at least. Thats all i can tell you as of now, hope i helped!