Two things are going on.

First the leaves - That is sunscald. It happens to plants that are raised under lower light conditions then exposed to direct sunlight.

Second the plant is experiencing transplant shock. This is a wound response from the roots being damaged during transplant. The plant has to pause it's rapid growth to heal it's roots and grow new ones. This can take a few weeks in severe cases.

Now for the good news - if the plant is sending out new dark green smaller leaves it's recovering from the damage and will eventually be fine.

First: don't listen to me, I'm an idiot.

This looks to me like burned leaves due to moving them into UV light without some pre exposure from indoors. New leaves shouldn't have that problem, but the growth seems to be stunted. Also Afaik the plant will start building new roots after transplanting, which will appear like stunted growth. Give it two weeks, the just might bouncec back. I transplant beans just fine but you should keep them outdoors from the start if possible.

So a couple things.

First, beans in start pots seems like a bad start to me. Not that I haven't also made this mistake, but beans (and peas, really any determinate annual) in my experience tend to struggle with transplanting. They do far better with direct seed, and even more ideally, with seed that has acclimatized to your growing conditions over a couple seasons. Starting them in trays or pots; you disturb the roots, the mixture will have a reduced flora/ fauna, then you stress them by moving them from a super comfy climate to a more stressful one. Beans tend to have plenty of storage tissue in their cotyledons to survive whatever they need to survive to establish.

Second, even though plenty of beans are indeterminate, most beans are determinate and evolved to be determinate. They die as part of their typical lifecycle in as far as they aren't usually continuously productive. It might be you are simply towards the end of the season on these? Have you gotten beans yet?

Third, I saw the other comment on inoculation, but really, rhizobium is ubiquitous in soils. Yes, there are plenty studies saying you'll get better results if you inoculate, but its by no means necessary to get great results. Just being in the soil is plenty of exposure to rhizobium if you've got healthy, mature soil. So, that begs the question: What kind of soil are you planting into? Is this yard soil? Yard soil mixed with potting mix? All potting mix? If so, how mature? How many seasons have you grown in it? If you have immature soil, and your beans are struggling, a surprising fix can be to apply a nitrogen fertilizer. This gives the beans more runway and more time to culture their own rhizobium colonies. When you harvest, don't pull the bean roots out. Cut the stems low and let them rot in place, and there will be plenty of rhizobium around in the future.

Fourth, beans are also subject to quite a bit of disease issues. They'll get rust and blight, and viruses. All kinds of shit. But also other issues can look like disease but its actually a management issue. You can often identify whats wrong by just looking at the pattern of damage being caused.

So lets look at your damage and think about how its happening.

You've got marginal (at the leaf edge) chorlosis (its not green any more) extending towards the leaf veins. The plant is trying to scavenge resources from the old leafs and is moving those nutrients to new leaves.

This is very typical in plants that are experiencing some kind of deficiency (like potassium). BUT...

It could also be a watering issue. If you have a soil pan that has formed (this can happen if you don't mix yard soil and potting mix sufficiently, it will develop a clay layer), the plant roots may have become stunted. This would also be consistent with having transplanted them (did they become root bound?).

So treatment..

Do you have any wood ash? If so, spread that around. Its rich in potassium and just, in general, plants love it. It wont hurt anything and if thats the issue, they should perk right up.

Also...

Whats your watering schedule? Are you watering every day? It could be that even if you are, your roots are bound to the top few centimeters of soil, and just don't have access to deeper water. Dig down into your soil careful and see if the soil has stratified. If this is a new bed where the soil hasn't been tilled very much by insects, this would be the first thing I would look for. Direct seeding in the future would mitigate for this. In the mean time, either top dress with more soil or water more often.

Did you inoculate the beans? https://www.gardeningknowhow.com/edible/vegetables/beans/soil-inoculants.htm

Beans need nitrogen fixing bacteria.