Not that I know of, NAT is only for (V)LAN --> WAN flows. I'm curious though, what is the design situation requiring internal NAT?
There's a router in VLAN B that I a) need to get traffic to/from and b) have no control over. The easiest path forward is to recreate it like the ASA that's being replaced and NAT the 4 or 5 VLAN A machines to a VLAN B address when traffic is destined for that router. Or all the time, really, it doesn't matter that much.
This is one of the reason I really have a hard time proposing Meraki solutions for any but the most basic scenarios. "Yes, I'm sorry, the $10,000 device we proposed won't do what the $3,000 device we're replacing did."
Yes, I know, we should let routers route and NAT. But still, between little quirks like this and the non-meraki vpn peer issues... I just wish it was a little better.