I would be worried about Esme not wanting to do anything if I was Sarah. I wasn't really a big fan of clubs/activities when I was a child and by Esme's age didn't go to any - but I was in school all day and had friends that I saw regularly outside of school. We did things without parents such as swimming, walks, shopping, cinema. There's also a lot more choice of activities now compared to when I was younger and if they are so well off then cost/equipment shouldn't be an issue.
She's said both Esme and Isabelle definitely do not want to go to school and don't want to go to any clubs, so should be looking at why and what they are actually going to do. Does she really think Esme can avoid any contact with people from outside the house and then function as a normal adult, make friends, form relationships and be able to cope with things such as job interviews and work alongside other people?
The reality is they will not join any clubs because it can't be vlogged, it costs money, and you have to commit some time to it. You can't join and then go off for months because there will be a waiting list for that place. They also have 1 car, don't seem to have much in the way of public transport, no family/friends around and live in a village with nothing there so the logistics of even getting at least 3 children to/from clubs that might be on the same days would be too much for them to handle. We've seen that they all have to sit around at home because Sarah has decided to go off shopping so no one else can do anything. Lots of people make it work if they have to but it would make much more sense for them to have stayed where they were before with good public transport and get a second small car to give them more options of splitting up. They would have had a lot of options of things to do in both Bradford and Leeds, with a train station just down the road and I'm sure buses going into both cities.
Jace could start at a school nursery after Easter, entirely for free and I think that would be really good for him to have some time away from the family, have some structure and routine to his day and make some friends. He could make a start on learning so that even if they decide not to send him to school at least he'd have done some basics taught a lot better than Chris/Sarah will be able to do. My daughter was only 3 (almost 4) and in nursery when the first lockdown happened and then in reception the second time the schools closed and it was far more difficult teaching her than getting my older child to do his work. There is no "independent learning" where you can just send them off to copy BBC bitesize, online zoom lessons she was bored after 5 minutes and needed constant attention to keep up with what was going on so no just getting a tutor and leaving them for an hour. There is no way Chris or Sarah would be able to teach the younger ones how to read and no way they will be able to commit to the next 18 years of homeschooling so at some point the younger ones will end up in a school and will be in an even worse position than the older girls.