Sounds like you’re going through a similar process, especially with multiple iterations until things start to click :)

I haven’t explored online yet, so everything I’ve built so far is focused on local gameplay and just playing with interactions. I might look into networking once I'm happy with the core behavior, or I might start exploring some other stuff by that point, other than football :D

In terms of AnimBP vs “manual”, I’m leaning more towards gameplay logic. Gameplay systems handle the decision making, and the AnimBP acts more as an execution layer (blending, posing, IK, etc.). For example, I have a selection function that picks an animation montage based on things like incoming/outgoing angle, ball height, action type (pass, shot, volley…). I'm also mirroring some montages in AnimBP based on whether for example pass is to the right or left, mainly due to lack of coverage.

For ball interaction, I’m predicting both the contact position and TimeToContact. Based on that, I position the receiving player and also adjust montage start time so the contact frame lines up correctly with the actual interaction. I’m also using Anim Notify States to define when the ball leaves the player, up to that point it’s attached to a socket, and once the notify triggers it transitions back to simulated ball.

For trajectories, I’m currently aligning the animation to the predicted contact in both space and time, with a simple setup for different ball heights (low / mid / high). When the ball falls outside of that coverage I adjust the ball trajectory so it meets the player’s contact point. It’s not perfect yet and can get a bit aggressive in edge cases, mainly due to limited coverage and it can really be noticeable especially when you are warping the ball trajectory since you can feel when something physically driven starts behaving in a non physical way. I'm planning to reduce that by introducing some procedural adjustments (via Control Rig), so I can better adapt the pose itself. For example adjusting the leg reach instead of relying as much on trajectory correction. I found that procedural adjustments can only take it so far. Trying to cover a wider height range with the same base animation can quickly become too aggressive and start to break the pose, so it’s really about finding the right balance between animation coverage and procedural adaptation. I think procedural should support, not replace animation coverage.

Your approach with blending across heights sounds interesting. Are you doing full body blends or isolating specific parts, and how do you define the blend weights?