I'm a vegan so experienced bean eater. There are a couple things I found that help, but they do come at a cost of flavor or texture:

Soak and rinse, but the soak water should be boiling when the dry beans go in.

Alkaline. Sodium Carbonate (baking soda) or calcium hydroxide (lime) work. Throw away the cooking water. This has to be done carefully, as too much of either can give the food a mineral taste and/or dissolve the beans entirely.

Fermentation also works. Lactic acid (like kimchee or pickles) helps a little. Koji (either added or grown on the beans themselves) helps a lot. Both will have a big impact on the flavor and what the beans will be good for in the end.

>Sodium Carbonate (baking soda)

I assume you meant Bicarbonate? Washing soda is pretty heavy duty and I've always used 1/4 tsp bicarb/lb of dry beans for dealing with old beans that won't soften the old fashioned way without any problems. You can also add the bicarb to the soaking water if making dry beans. Discard and rinse, as usual.

I'm not very familiar with this topic. What is the chemical mechanism through which you feel that baking soda reduces undigestible sugars in beans?

Rhizopus oligosporus (tempeh) worlds pretty well too!

What’s koji?