The short answer is yes, you and every other footballer should be lifting weights in-season.

Now that is out the way, I think the question we should be asking is "how should you lift weights in-season?"

I believe strength training sits somewhere on the scale of performance enhancement and injury prevention.

Sometimes sessions are going to be more geared towards performance enhancement, typically sessions that are furthest away from the game, when there is more time to recover. Other times they are going to be done more as an injury prevention stimulus, most likely during congested periods with lots of games.

When training for performance enhancement you are typically going to be working at a higher intensity for more reps and sets (volume). This is because to improve performance you need to provide the body with a stress that is great enough to actually drive an adaptation. This obviously comes at a cost as you need typically between 48-72 hours to recover from a strength stimulus (I'm sure you are aware of what DOMS feels like!).

On the other hand training for injury prevention is typically going to involve a micro-dose of strength work. The intensity can remain relatively high but you should drop the volume right down, 1 set might even be enough. Due to the lower volume the fatigue and recovery time associated with these micro-dose strength sessions is going to be much lower which make them a great option when there is only a few days between games.

It is worth noting that it's never either-or. All strength training is for performance enhancement and injury prevention. Sometimes however, the focus is on one more than the other.