Looking atExodus 21, I do not see your point.
The KJV, DV, AND Wycliffe all use the word servant and follow the Sabatic rules.
I think I've heard that the newer interpretations use the word slave, but they have a lot of other mistakes too.
Here is a link to a Jewish site and as you will see they use the word servant too.
https://www.mechon-mamre.org/p/pt/pt0221.htm
If it is just servant and not slave then why does it say the slave/servant is his money?
20 “When a man strikes his slave, male or female, with a rod and the slave dies under his hand, he shall be avenged. 21 But if the slave survives a day or two, he is not to be avenged, for the slave is his money."