I want to start some strawberry seeds.

From about 50 seeds that i previously planted only 3 sprouted , but these that did are developing very well.

from what i read in many websites i understand that high temperature can cause the seed to remain dormant and even go into a deeper dormancy state.

I was looking for a propagator that can control the temperature , but where ever i look i only find ones that can provide heat (maybe for cool climate).
I can't find a propagator that can cool down and provide a cooler environment then the one outside.

Is there such a propagator ? (one that can cool not just heat)

It might seem difficult to avoid high humidity without clobbering light input, such as by using clear plastic as a vapor barrier or as a water bag, but it's not too hard.

That's one way.

You could dedicate an old mini refrigerator (dorm room fridge) and apply some mad skills vis-à-vis copper tubing coils, a thermostat (even a pair of lowly snap discs), a teeny little pump, and so on. Plants could sit right on top of the refrigerator cabinet.