Can alterations be made to this dress to take the beading off?

You have to talk to a local seamstress to find out. Most beads are sewn on so it shouldn’t be impossible, just time consuming.

I would say it might potentially damage the dress to remove so much beading.

They might need to replace the sheet panels all together. I assume that would be possible, but might be expensive since it would involve essentially taking the dress apart.

I would keep looking until you find a dress that only needs fitting alterations, instead of design ones. Why pay for the beading and also pay to have it removed (assuming the removal would even work without damaging the look of the dress)?

Agreed with this. I would keep looking if you want to make drastic changes to the dress. Seeing if you can order the dress without beading is an option as well. I don't think its possible to remove that much beading from sheer/illusion fabric without damage.

You wouldn't be able to remove the beads without damage. You would need to replace the mesh from the back. This type of alteration can be expensive with normal alternations. So I would ask for an estimate. Or I would look for another dress or reconsider the beads if budget is an issue. If budget isn't an issue then go for it.