Router Filter Causing Insane Lag

[Right Side Gone]

Basically i was hit with an error after updating fortnite that i was blocked due to firewall issue. I forwarded ports and issue was gone. Few hours later i forwarded apex ports, and returning to fortnite i get incredibly unplayable stuttering whenever i encounter enemy players.   At first i thought it was a port issue. But after turning of ident port 113 filter, the problem is gone. The issue is ident 113 is enabled for security purposes. Leaving disabled troubles me, as it affects my entire network .not just my gaming computer. I am using wifi connected to a linksys smart wifi router. I have never had an issue on fortnite with any other machine. I have never needed to forward any ports at all. Leaving ident enabled causes stutters ad mentioned, but also halts texture rendering and causes polygon like building for a minute or two. Whuch is completely internet related with fortnite. That im certain of. Any help is appreciated.