Hamstring strengthening for running (or related activites/ sports)?

You can also do glute bridge slides, don't let the name fool you as they kill the hamstrings. Squats in general help but aren't targeted. Hack squats will generally help a little more but many people don't like those so that is your call, I find them entertaining enough.

My two cents.
Constestualization is the key. For exeample, when my focus was to run an halfmarathon, I have no time to do strenght exercise for legs. Following a specific scheduling to half marathon, I ran 4 days during the week and there was not time to add other leg work. As a matter of fact my training it's focuse on resistance. On other side, if one want's focus on short distance, the power and explosivity are more important and it's normall to strenghten legs.
You can compare the body type of top 100 meters runners with the one of top marathon runnes.

Anyway, a lot of exercise works on hamstring: e.g. squat (and its' variation), deadlift, kettebell swing. There are also specific exrcise focused on hamstring like nordic hamstring.

I was thinking the same thing. I tried looking for hamstring exercises and only found 2 or 3 - I'm not sure because they were part of regular workouts with lower body focus.