I have 4 small chili plants (sorry not sure what variety they are), they have 3 sets of leaves. I re-potted them from a seed tray about 2 weeks ago. I'm a bit concerned the plant pot is too big? When growing from seeds how many times should I re-pot and into what sizes?
That would be the smallest pot I would use for those plants. I only re-pot once (from the seed tray). Of course re-potting disturbs them and sets them back a bit. Also the roots can get tangled (hence the disturbance).
Over the last 2-3 years, I've come to the realization that peppers do much better in raised beds or normal beds, rather than pots. I have had reasonable size adult plants in pots that size or larger (pepperocini come to mind, although this year's are slow growing), but they tend to be the exception.
Ornamental peppers seem to do fine in pots as well, but ornamentals are generally smaller plants to start with.
Of course pots might be the only option, in which case I think you have to live with smaller plants and less fruit.
To me that pot looks about big enough for 1 plant. And only with daily watering care if it is hot. Even if that many plants "work", you won't get more peppers from them than from 1 big healthy plant.
I usually repot once directly to my main growing locations. I may put left overs into medium sized joghurt cups to give away or repot again eventually, but there seems to be no difference in which plants do better.
I think the pot is big enough. I am growing about 6 or 7 plants in a pot smaller than that. I get about 3-4 chillies every month from each pot( i have 3 pots) . Its my first time planting chillies and I don't know how much they grow. They have stopped growing now and they are about 1.5 feet high. I think your pot is big enough.