If you would like to transfer money in a foreign currency or to a country outside the Single Euro Payments Area, you must make an international transfer. When making an international transfer at your bank, you fill in a special form. You can obtain this from the counter. Transfers to Ukraine may incur fees as Ukraine is a non-EU country. These fees may be charged by both the bank in Germany and the bank in Ukraine. On the form, you can specify how the costs should be allocated (either the recipient or the sender pays the entire fees, or the costs are split between the two). The cost of an international transfer varies from bank to bank. You should therefore ask your bank in advance. There are currently often special conditions for transfers to Ukraine.
Note: An international transfer may cost up to ten percent of the sum being transferred. So if you transfer €100 to Ukraine, it can cost up to €10.
More info: https://www.verbraucherzentrale.de/wissen/vertraege-reklamation/kundenrechte/neu-in-deutschland-was-fluechtlinge-aus-der-ukraine-beachten-sollten-71305
Money transfers using Western Union or MoneyGram may be slightly cheaper. Here, you pay an amount in euro at the counter and within a few minutes the recipient can collect the amount in hryvnia from a location of the respective provider in Ukraine. Often there are no conventional fees, but the provider earns a profit on the currency exchange. It is therefore worth asking about and comparing transfer fees and exchange rates beforehand. This can be done, for example, on geldtransfair.de.
Western Union locations in Leipzig: https://location.westernunion.com/de/sn/leipzig?country=DE&q=leipzig
MoneyGram locations in Leipzig: https://www.moneygram.com/mgo/de/de/locations
Note: Due the to war, it may also be difficult for banks and money transfer providers outside the warzone to maintain normal operations. There may therefore be delays when making money transfers.