There are a few such strains, however, I find them difficult to obtain consistently.
I have taken instead to purchasing high quality hemp flower whether it be CBD, CBN, or CBG centric strains from places like WNC (google it). I then purchase whichever typical THC dominant strain that I am interested in at the time. I typically grind 50% hemp flower and 50% THC flower and mix them together into a container. I then draw from that container for use(s).
This method has been life-changing for me....a person who does not want to be completely snookered but benefits from the mild(er) effects. It still doesn't take much material (for me) to have the desired effects....and flower lasts me a long long (perhaps too long) time.
Personally I find the CBG flower to be a great accompaniment for my needs. I often purchase a CBG strain called "Oregon White" as my primary mixer.
The type of strain that you are seeking exists, however, it seems that it is not among the most marketable strain types thus dispensaries do not consistently stock it and growers do not consistently grow it (at least in my area). Most folks are looking for the high THC materials. 'Making your own' 50/50 mixture does require a very small amount of effort, however, it allows you an endless array of combination opportunities and you ALWAYS have your option for a low(er) THC and higher CBD material. Of course you can also change the ratio of CBG flower to THC flower to specifically suit your needs.
YMMV....but to me this is 'the way'. If you are looking for popular strains to grow CBD....I'd review sights like https://wnc-cbd.com/
and others to see what is being grown by the big sellers. They even have descriptions which may include the source of seed(s) for that genetic.