Design Firewall FG and Layer 3 Switch

Hello

I'm trying a new setup, I have a border routers with eBGP peering to our ISPs. Nats to my local network and some route maps. On the inside i have iBGP and HSRP peering to "Cisco Asas"

"Cisco Asas" now have the VPN concentrator and the inter-vlan routing from all the local Lans connecting the Layer 2 access switchs.

But now, we need to concentrate all the inter-vlan routing on Layer 3 switchs on the access, and add a better supervision to the North South traffic with a Fortigate. What is the best way to achive this; if the Fortigate doesn´t have the inter-vlan routing?

Thanks to all for the time and support!!!  Hope they have a good day!!!!