Is renegotiation possible for a home loan?

The termination referred less to the home loans and more to other investments with the bank.

Just to understand, you want to use the overall relationship as leverage to renegotiate a binding contract without a unilateral termination option to get better conditions?
Go ahead... if you think it's the right thing to do.

It regularly happens with us that old (still ongoing) loans are refinanced through new financing. Then the customer pays the actual damage we have due to the new refinancing, or simply finances it and enjoys the relief of his liquidity.

That may be so, but it's about reducing liquidity, i.e. the installment. The bank compensates for that with the termination fee. The OP wants to simply have it cheaper. If he has to compensate the interest damage for that, he wouldn't have gained anything.
Or am I misunderstanding this right?

Or am I misunderstanding this right now?

It is always a calculation exercise for the customer. He has to pay the compensation here for about eight years. However, he may be able to buy himself a better condition for 20 years.

I don't want to use any pressure tactics at all. I have no pressure because I have solid financing with a valid contract (and no real pressure tactic either) because one thing must be clear: NONE of us are so important to a bank that it throws its absolute rules and principles overboard for us. We are all absolute small and very small customers and often rather pleasant accessories. I tend to agree with the other opinion: Go there, talk nicely, listen, and ask politely. If the answer is no: OK, then I still have another 13 years of absolutely secure interest rates, possibly use my special repayment to reduce the remaining debt, and that’s it. If the bank wants to talk (e.g. about an extension of the term): Great, we'll see if something positive can come out for both sides. If nothing comes out, I may have just had a nice 1-hour conversation with someone and probably drank 1 coffee and 1 water.

My employer does not negotiate. Give and take. They are not at the Turkish bazaar. Or would you go along with an upward adjustment from the bank side?

My employer does not negotiate. Give and take. This is not a Turkish bazaar. Or would you participate in a bank-side adjustment upwards?

Possibly yes, for example: The financing at 1.8% has been running for, say, 9 years and is fixed for another 6 years, but interest rates are now at 6%. The bank asks: How about we refinance now for the entire remaining term at 2.5%? That is exactly your example. I would definitely consider whether they would agree to the upward adjustment...

My employer does not negotiate. Give and take. This is not a Turkish bazaar. Or would you participate from the bank’s side in an upward adjustment?

The banks and building societies are constantly trying to get rid of well-interesting investments like old building society contracts, etc., and to talk customers into giving them up...