Please do. Given your other information, I think this is the best option for getting this to work on your current machine. By the way, this parameter is called --p-reads-per-batch (I think @Mehrbod_Estaki may have been referencing some old documentation when he mentioned chunk size)
Perhaps it is not configured correctly? You should check how much memory the job is actually using, and the maximum amount available. It is a little suspicious that this worked for you on a less powerful machine.
Do you have access to the old machine that already has that release installed? You could also downgrade conda if needed but that is probably not a good idea — it sounds like this is an issue with the hardware, not with the QIIME 2 version or with the classifier itself.