please don't post these log records to the forum - you already used the "send to support" button to send this log record to me about one minute before posting it here.
So I'm going to reply to your email now - in german, which seems more appropriate in this case. ;-)
For the record: The reason why eBay returns this error is the fact that (for some reason which I still have to figure out on your site) you send a price value using a decimal colon instead of a decimal point to eBay.
19.99 you send
19,99 as StartPrice - which is quite strange and can't be caused just by using WooCommerce in german. There are many german users, but none of them had this issue. Do you have any plugin installed that could be messing with the price format in the database?
Anyway, let's continue this via email...