16GB is enough for three 2GB Linux VMs.

Yes, upgrading to 16GB will let you add a third VM without issues.

Here’s the breakdown. Your host needs maybe 2GB to run itself (more if you’re running a full desktop, but still fine). That leaves 14GB for VMware. Three VMs each with 2GB RAM = 6GB allocated. VMware adds a bit of overhead per VM (maybe half a gig), so call it 7-8GB total. You still have 6-7GB headroom for host apps or burst usage. No swapping.

With 8GB you were running two VMs at 4GB allocation plus host – that’s tight. Any extra load would hit swap. Moving to 16GB gives you plenty of breathing room.

One thing: if those Linux VMs are actually memory-hungry