There's nothing wrong with adding them, but it's worth realising that pulling strength is fairly universal; if your vertical pull strength is strong then your horizontal pull should also be fairly strong. To a certain extent, you won't have one without the other as they use largely the same muscles. The good thing is you don't have to overthink it. Sure, switch things up and add these if you're psyched, but as long as you do one or two compound pulling exercises each week, you're covered (3-5 sets to maintain, 5-15 sets to improve).
Of course, if the goal is to get better at climbing, then nothing beats climbing. If by pulling into the wall you actually mean improving body tension, then you could get on a steep wall on good handholds and move your feet around in extended positions, prioritizing poor footholds, supplemented with posterior chain exercises (glutes, hamstrings, calves, lower back, etc.)
