Debussy and Accents
I see Debussy’s use of accents here more as a grouping factor rather than a hierarchical one. The burgundy-circled accents (tenutos may have worked just as well here) occur where a different type of emphasis might be more intuitive. I believe he used these here to keep one from making the two sets of sixteenth-to-eighth notes from being performed the same, i.e. with a heavy fall towards the eighth note. Because of this, the main beats are emphasized, rather than the syncopation.
I see the green-circled accents, and the accompanying dynamics, as ones that prevent these notes from being played as “resolution notes”, i.e. softer. Again - a negative marking, telling you what not to do rather than what to do.
I think Debussy changed the c-flat accent here to distinguish this from the two preceding c-flats. The earlier ones “stop” the action, while this one is the launching point for the following note.
This chord, although written with an interesting harmony, is mostly a percussive attack, as directed by the multitude of directions around it! 1) the crescendo coming from più forte; 2) the staccato; 3) the accent; 4) the sff. That is a lot of information for just one event! The following measure of silence is thus set apart and quite dramatic!
So, in actual playing, I don't know that I would "distinguish" these accents - except for the last one - but rather view and play them with an understanding of how they band certain events together.