I don’t know for sure but it could be a problem with the trim calculation. They have been like that since they were introduced - on my first go on an RR variant I thought there was a serious flight control issue when it came to rotate as the forces were so much higher than the GE versions.
For quite a while as SOP we added some back trim to the FMC value to bring it closer to the GE experience but Boeing got wind of that eventually and put the kibosh on it. I joke about having developed a specific set of exercises to do in the gym before a RR flight but it does catch people out who are new to type and haven’t experienced or been briefed about it yet.
I don’t think it’s anything to do with the engines themselves, just (IMO) the trim setting algorithm in the FMC is getting it a bit wrong but the aeroplane flies so no-one can be bothered to fix it. A bit like the blockpoint update which left the plane much worse at holding than before that hasn’t been improved since.