It does look like edema to me, due to the bumps on the undersides of the leaves. However, spider mites could be accompanying the edema. Also, alternaria, anthracnose or similar fungi might lead to similar yellow spots on foliage.
To help prevent edema symptoms, you can try the following:
- Add some ventilation. A very small fan or vents to allow outdoor air to come in should help. A big fan may cause your soil and plants to dry out quickly (especially if it's warm; that's kind of how food dehydrators work—fans and heat).
- If the room is warm and humid, making it cooler and dry should help (although warmth and humidity can be good for plants).
- Don't crowd your plants. Crowded plants are more susceptible to edema.
- Don't get the leaves wet. I've had a plant that seemed edema-free; then, I got the leaves wet, looked away for some minutes, and when I looked back it had really, really bad edema all of the sudden. Water seems to be able to be a trigger.
- Don't stress about it too much. If it's just edema, you probably shouldn't throw plants away or anything like that. I did that with a tomato once when I didn't know what was wrong with it. It had edema much worse than your plants, but it would have been fine. I thought it might be a contagious disease or something. It's possible a fungal pathogen is involved, but I wouldn't worry about it overly. You can learn from the experience. I would work more on prevention for next time, improving conditions for now and such—rather than striving for all-out perfection right now (although it is possible the pathogen might cause issues later if/when conditions become favorable for it outdoors, if it's still dormant on your plant—which is possible, but you can always pull it up, or something, if that happens to a problematic degree).
I'm guessing you just barely put the plants in your greenhouse. If so, the problem will likely go away soon (on new growth). If not so, I wonder if there's a lack of ventilation in your greenhouse, or if it's too hot at night (if it's warm, humid and dark without air movement at night that might increase the likelihood of fungal pathogens). My greenhouse is unheated (so it's much cooler at night); same for outdoor humidity domes. I'm not sure if that's why I've only had plants with edema issues indoors, but it's worth a try, perhaps (as long as you don't damage your plants; some people think damage from cold can contribute to fungal pathogens; I guess it really depends on a lot of stuff, though).
Ventilation (air from outside) in humidity domes and smaller greenhouses is supposed to be important for transpiration, I've read (and I've noticed that plants won't grow—and in fact can dwindle—and that seeds won't sprout, if there are no open vents on the small greenhouse). I don't know how much of an issue this is for a larger greenhouse, but it might be worth investigating.