For which I can’t find anything in the I2C spec about doing that (I checked) which means that it is unlikely any of the major firmware API’s like STM32 are going to have support for “write to register but don’t actually send anything to write”.
I use I2C as a comms mechanism between MCU’s and Pi’s and it has never occurred to me to try that sort of sequence.
Maybe @litbos could evaluate a mainstream sensor with more mainstream I2C support? It would be a shame to rule the RAK range out, as I can’t image you’ll find another vendor range that uses well supported API’s that will enable this.
PS, Arduino based I2C doesn’t count, I can hack that as much as the next hacker to warp time & space.