Anti-DDoS Pro and the WAF are fully compatible.
Anti-DDoS Pro IP address (entry layer, for Anti-DDoS protection) > WAF (intermediate layer, for application layer protection) > origin site
Enter the Server Load Balancer Internet IP address, ECS Internet IP address, or off-cloud server IP address for the origin site. Select Yes for Other proxies enabled already? and click Next.
Configure Anti-DDoS Pro.
Modify the domain name or add a new one. Select Origin site domain and enter the CNAME address generated by WAF.
Change the DNS resolution and point it to the CNAME address generated by Anti-DDoS Pro. This causes the website traffic to first go through Anti-DDoS Pro and then be forwarded to WAF.