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You have pictures of the surrounding location?
Water evaporates pretty quickly from the top soil, and everything below 1" should drain quickly for pepper plants.
If you have dense clay soil, it may be retaining water and keeping things wet. You need to mix it up with Soil Amendment every year between plantings to ensure you have well mixed and balanced soil.
Add some amendments like perlite, LECA, pumice, whatever. They don't absorb as much water and make the soil more airy, preventing root rot
How often are you watering? Is it by hand or irrigation system? Is there runoff, e.g. from a nearby lawn? If the issue is your soil drains poorly, you might be able to condition it by breaking up any compact soil and amending it with organic matter (and maybe sand). However this is fairly labor intensive and takes time to do properly (and might not fix the issue, depending on the cause). Building raised beds might be a faster and more effective solution.
Peppers have a fairly small root ball, so you could always grow them in grow bags (I'd recommend one 10 gallon bag per plant); it's nearly impossible to over-water grow bags (but on the flip side, it's very easy to under-water them!) Plus growing them in bags makes it super easy to overwinter them, assuming you have access to a garage/basement.
Would you presumably use grow lights during the overwinter process?
I've never done it before because I lack the facilities, however this video goes over the process:
How's the drainage in the plots? Are they in ground or container?
I am still pretty new to this, one is in a container which does have some big holes on the bottom and the other is in one of those self watering pots.
I would of assumed drainage would be decent.
Where on the plant are the leaves yellowing?
My first guess would be transplant shock. When the roots are damaged the plant has heal them. The plant needs to uptake nutrients to repair the cells and grow new tissues. The problem is the roots are damaged and plant struggles to pull nutrients from the soil. So the plant moves mobile nutrients (like Nitrogen) from older leaves to the new growth.
The solution is usually to give the plant some fertilizer and wait a few weeks.