Loading an area
The Anchored Pearl loads a 3x3 area of chunks around itself. But be warned the powers of chunkloading powers of the end are not tamed so easily.
The pearl is only able to stay in the same place for so long by itself, it stays in the same place for up to an hour. After that it teleports away, leaving a kind of ghost imprint behind. This ghost imprint can be used to find where the anchored pearl teleported to (right click on it).
Each pearl will chunkload the area for 9 hours and will shrink as time passes until all the power is gone and it vanishes.
Framing the Anchored Pearl
To prevent the Anchored Pearl from teleporting away you can build a frame with the Anchored Frames.
You can make Anchored Pearls my smelting Broken Anchored Pearls