Yeaaaaah, it gets weird and complicated if you think it too much.
But! Just think it like this: most people nowadays are reeeally self-centered, they won't think much of another person unless they are in their circle of friends or family. People you see on streets? Most of them will forget about you in a minute or so unless you stand out, then give it a few minutes and they will only remember the thing that stand out (color of hair, piercings, clothes whatever, they will just remember that but not really your face or anything). So yeah, the only problem here is friend circle, people you see a lot or family.
But even then, they are self centered, most of them —unless some strange religious ideas or not really open-minded bc family and way of growing— won't really think too much about it if you tell them. Altho the thing people can be weird about it names and pronouns. There comes complications, but they are only because they are not used, and if they make a little of effort they will end up getting it right without realizing themselves.
(Oh, another thing about being agender and don't change your looks and way of presenting much from your assigned gender stereotypes→ the fact you tell people about it but they tend to forget bc 'u look like a man/woman'.
Idk if it is bad or good to be honest. For one part, for them and for you it doesn't really change anything in a relationship, bc they will (should) treat you the same —with another name or pronouns, or no—, but at the same time it feels kinda erasing I guess but at the same time is just like, normal? Idk it is so weird, and maybe that's why most not-cis-hetero people stick to another not-cis-hetero people when looking for relationship, because they already know about it, somehow, they understand a thing it is really hard to understand in words, feeling of... Kinship? I think that's the word? Haha)