I’m not really sure what you’re asking when you say “reverse the order”.
Normally, you just hit reply and if using Gmail, it keeps them all together in stacked form in one “conversation”
However, if you hit reply but change the subject line, that breaks that conversation group and begins a different one.
Same thing if you hit compose instead of reply that also starts a new chain and then also reversesv the order because you would then be the sender to whom the rest of the replies are sent. Is that what you mean?
Are you trying to prevent overly lengthy chains and break up into more manageable smaller groupings or what?
But that’s Gmail methods. Other email programs may handle things differently.