Does speaker toe-in affect reflection points?

Be careful not to confuse sound from the first reflection with the direction of maximum reflected sound or the direction of maximum sound. They are all different.

Speakers generate sound waves in all directions and every driver/enclosure combination has a different pattern (dispersion). The first reflection on the side wall is that point which reflects whatever sound waves from the speaker are hitting it directly back to the listeners ear. This can be determined geometrically on paper or with a mirror and is independent of the speaker's dispersion or its toe in.

As soon as you begin to toe a speaker in (assuming you do not change the position of the driver), the level of the sound hitting the first reflection point is reduced (assuming as is true for most speakers that the horizontal dispersion falls off to both sides of the driver). So, the effect is that you will hear a less intense first reflection and hear a more intense direct level of sound from the speaker. Also, as you toe in, the level of sound directly hitting the entire wall is reduced, and more of this energy now reflects off the back wall.

If u read up from real trap website on first reflection , based on the mathematically formula on how to calculate first reflection, shifting the speaking forward by 1 ft and toe in by few inches hardly change the first reflection point. Happy listening

Two additional points to complicate your considerations.

First, the first reflection point to your ear is the floor in front of the speaker (it's closer). So changing wall reflections points cannot be considered in isolation. Any effect may be lost or amplified by the interaction with other reflection points, particularly closer, stronger ones.

Second, different frequencies are bounced, absorbed or partly abosorbed depending upon what it is hitting. So the composition of the reflection point is as significant as its location.

So in other words, just fiddle around with it and see what you like. Speaker manufacturers are also a good source of information as whether their speakers should be toed in or not, and by how much.