> appear to be straightforward imports from sphlib ( http://www.saphir2.com/sphlib/ ), with just the license removed and replaced with their own.

That is so blatant:

https://github.com/tronprotocol/java-tron/blob/develop/src/m...

https://github.com/jnorthrup/sphlib/blob/master/src/main/jav...

It's written right there in the license block they cut and replaced "The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software".