Good advice, HBWR seeds are more practical, but I also still think that extraction is worth looking into as well. It can be very modest, just get some HBWR seeds (Hawaiian Baby Woodrose) and absolutely smash them or grind them, little grains is okay but making powder is ideal. Then get it a little wet, best would be to more than saturate them with water. Let it stand for a while like maybe half a day? Then hold the pulp under your tongue.
It's optional to steep, let it dry and scrape a few times. You might wanna use more water for that and make it acidic even. I would think making a crude extract would make it easier to take it sublingually.
Oh and sorry your original question: it depends on the pesticide but I think yes, they would probably be absorbed. But definitely not all morning glory seeds are coated with stuff like that and if you get HBWR in the right place they aren't either. So you can find a way around that.