My own feeling is it's best to leave it as it is - that is, exactly as it came out of the factory. That you can't read it doesn't matter: You know it's there, it's compliant with the law, it's "original" as the bike was supplied to you and it hasn't been altered.
To slap these ebay stickers over your bike might suggest to plod that you're trying to disguise or hide something, even though you're not.
My own e-bike has four lines of incredibly small text at the very bottom of the seat-post, printed in white over a silver metallic frame colour. It's so difficult to even see never mind try and read, and it took me a good while to even realise it was there. But it is there, it's as the manufacturer printed it, and it shows the bike and labelling is compliant. All I need to do is point to it if I get stopped! That seems a better defence that trying to argue your non-original sticky label does in fact represent the truth, the whole truth, and nothing but the truth!