Someone on the Magic Discord posted this and I've confirmed it via testing.
When applying a BleedEffect to an entity via #setEntity it follows the entity around as expected, but is always XY centered on the block the entity occupies, instead of being centered on the entity itself. This may also affect other types, although at least SphereEffect is not affected. I assume this is a rounding error somewhere, but couldn't find it.
The BleedEffect uses a block break particle by default, for which it seems the client aligns its origin with the nearest block center. A more desirable alternative might be a Redstone Dust particle.
Someone on the Magic Discord posted this and I've confirmed it via testing.
When applying a BleedEffect to an entity via
#setEntity
it follows the entity around as expected, but is always XY centered on the block the entity occupies, instead of being centered on the entity itself. This may also affect other types, although at least SphereEffect is not affected. I assume this is a rounding error somewhere, but couldn't find it.