ubuntu only use 8 cpu for RX and TX queue with vmxnet3

You can change the number of queues at runtime. So, check the limit of queues with ethtool --show-channels ens192, and then change the number with ethtool --set-channels ens192 rx N tx N. Note: the way above isn't applicable to the vmxnet3 driver due by lack of this feature support.

UPDATE: after inspecting of source code of the vmxnet3_driver I've found, that maximum queue count is 8 (https://elixir.bootlin.com/linux/latest/source/drivers/net/vmxnet3/vmxnet3_int.h#L306). The number of queues depends on the cpu count (https://elixir.bootlin.com/linux/latest/source/drivers/net/vmxnet3/vmxnet3_drv.c#L3398). But it cannot exceed the hardcoded value, obviously.

UPDATE2: I've checked the source of vmware-tools. The driver from it has other limits: up to 32 queues (https://github.com/vmware/open-vm-tools/blob/master/open-vm-tools/modules/shared/vmxnet/vmxnet3_defs.h#L636). So you can try to use it.