Stop sanding - that's going to give you a fresh problem also needs to be resolved.
Instead, try peeling off one of the decals - I think this cracking is more like crazing in the white only. Noone's come up with a structural sticker (yet) so peel one off and see how it looks underneath. Some very gentle warm air may help soften the adhesive.
The black base layer cracks may also have a transparent sticker or anti-rub patch in place there.
If you want a wordy bike, then both reproduction water decals or vinyl-cut stickers are available all over, to apply after you clean and fix the paint layers.