2-3 years before buying a house: Does it make sense to consult a financial advisor?

Be a little patient and wait for the next correction, then invest a nice portion in Bitcoin, Ethereum, Cardano, etc :-)

Would it be worth investing in ETFs or something else for 2-5 years? Of course, there is a small risk involved, but for 1% interest, that would be just a drop in the bucket.

It can be worth it, but it can also totally backfire if after 3.5 years you come across the perfect property, your partner also suddenly really wants to build, and the index is just in the basement at that time. ETFs make sense for investment horizons of >=15 years or more. Otherwise, given your risk appetite, you can simply buy Amazon and Tesla shares directly.

That is quite a short investment horizon. If there is a big dip next year, you might end up with 30% less. If you want to build in '22, that might not yet be compensated for. With 5 years, it looks somewhat better but basically the advice is to shift the capital to low-risk once you approach the time of use.

Overall, the situation is currently extremely difficult to assess. The economic fundamentals are poor and realistically not much will change before Easter. At the same time, the stock markets jump from one high to the next as if nothing happened. There are two explanations for this:
1. a bubble that will burst soon
2. thanks to the financing of the Corona aid through the (virtual) printing press, this is now "normal" and the money is simply worth much less than a year ago.

In the first case, you should not jump on the bandwagon, in the second case... I don't know. Existing ETF savings plans I would continue, but if you need the money in 2 years neither of the two explanations is really cool.

Does it simply mean putting the amount into a savings account with 0.5%?

I will probably skip the financial advisor then. It is rather discouraged for my plans.

0.5% for the overnight money is still good, I think I am significantly below that. But I'm doing something similar right now with the money intended for the house construction. There is no reason to risk any losses in the last six months, especially in a volatile situation. With medium-term time horizons like the mentioned 2 years, it's the hardest to decide. Also there, tend to take less risk and earn a few euros less than risk a bigger loss.

Financial advisors can be useful if the initial situation is complex and they really provide advice. The problem is that almost none of the so-called financial advisors are paid for their advice but live off commissions for sold products, ergo they are salespeople. Like vacuum cleaner salesmen but for larger sums. And both the fee for an advisor and the commission for a salesperson have to be earned first in the end. Since in the long term no one beats the market but many perform worse than the market (especially because they chase trends), the only sensible advice for long-term investments can be to invest broadly diversified in stocks (e.g. through a low-cost ETF savings plan) and then not worry about it too much.