The Superhero Database Classification number, or SHDB Class, is a number that represents the overall 'power' of a character. All traits of a character are used for calculating the Classification.
What it DOESN'T mean
This doesn't mean that a higher class would always beat a lower class character. But the bigger the difference in Class is, the more obvious it is who'll win in a fight.
How is this calculated
( INT^1.3 + (STR*0.5 )^2 + (SPE*0.5)^2 + DUR^1.6 + (POW + (SPS*SPL))^2 + COM^1.8 ) ^ TIER
Super Power Score and Level
Every Super Power has a score (SPS) that is used to calculate the Class. Each Super Power also has 3 levels (SPL). The level is set when connecting that Super Power to a character. The level determines the final score, of the Super Power, being used in the calculation.
From where Eren with FT exists in the World of the Paths, beyond both space and time, he could control causality and the very plot / the future itself, simply by manipulating the minds of numerous eldian beings (both humans and titans) who existed on a lengthy timeline along thousands of years of history, therefore ensuring that the story would eventually play out in exactly the way he had foreseen as the Attack Titan.
That's just almost author-like transcendence and power to control the plot, and I would certainly and consistently scale any character with such a powerful meta-ability at least to 5-D or more - not only Eren.
Scans
Transcending Space:
Transcending Time / Seeing all times past + present + future simultaneously "at once", just like only a 5-D+ being would and could:
my question: Do Eren Yeager and the Founding Titan have a considerable level of control over the causality and plot of the story
Answer by AI:
Yes, Eren Yeager and the Founding Titan have significant control over the story's causality, especially in the later parts of "Attack on Titan." Eren's connection to the Founding Titan allows him to influence the memories and actions of other Eldians, as well as manipulate the flow of events in a way that shapes the overall narrative. This ability raises questions about free will, determinism, and the impact of historical events on individual choices. It creates a complex interplay between fate and agency throughout the series.
I've read the manga and watched the series multiple times, it's one of my favorites of all time, so I can really only agree also with how AI puts it into words.