The original I2P has being (and is being) developed in Java - which to me, always seems, completely unsuitable for smaller ARM machines due to overhead. In fact my experience has been that unless you run Oracle’s Java, things are a bit hit and miss. This version is developed in C++ so it’s not going have the processor overhead of a JIT and (presumably) can give us similar protections. Unlike Freenet, there appears to be a more active community behind i2p.
The other difference is that after three failed attempts at the Java version of I2P, I was ready to throw my daily driver out of the window. The I2Pd worked first time, flawlessly!
I2P offers many of the same protections as TOR but inside its own ring fence.
https://i2pd.readthedocs.io/en/latest/
This system may only work for desktop installations rather than as router/proxy for all the machines on the network but that’s WAY over my head and I leave it to others to decide if this is worthwhile.