RTL8218 datasheet

Hi guys
I am looking for the RTL 8218 Data Sheet.
You have this data sheet.
Meanwhile, I have a Data Sheet RTL8218B. I asked if it would be different with the RTL8218 chip.
Or one.
Thanks if someone can guide you.

In general, a letter suffix on a semiconductor relates to internal changes rather than external functionality - the pins and external signals should be the same.

From a user point of view there is rarely any significant difference.

As you have found, there does not seem to be a data sheet for the non-B version of the IC, so it's difficult to know what the actual change was.
It could well be something like lower power consumption compared to the the original, though that is a guess.