there is no law requiring you to register in the UK
You’re talking bollocks.
"What happens if you do not register
You must register to vote if you’re asked to do so and you meet the conditions for registering, for example you’re 16 or over and you’re British or a national of an EU or Commonwealth country.
If you’re asked to register and do not, you could be fined."
In Germany you have ‘meldepflicht’, but there is no law requiring you to register in the UK.
You’re talking bollocks.
"What happens if you do not register
You must register to vote if you’re asked to do so and you meet the conditions for registering, for example you’re 16 or over and you’re British or a national of an EU or Commonwealth country.
If you’re asked to register and do not, you could be fined."
– https://www.gov.uk/electoral-register
Can you find a single example of a fine occurring?