Real or fake? Interesting error coins on ebay

First: A 10 kopek coin that has a 5 kopek pressed on it? I am extremely confused. Never seen one before.
https://m.ebay.com/itm/10-kopeck-kopeken-0-1-denga-rubel-rouble-1809-Tsar-Alexander-I/112658674727?_trksid=p2141725.m3641.l6368

Another weird one, what is this?
https://m.ebay.com/itm/Finland-Russia-Silver-Rare-Error-Alexander-II-Monogram-Struck-on-1870-2-Markkaa/201718968959?hash=item2ef763327f:g:l0IAAOSwiDFYKuxl
And another one. Quite pricey. What happened?
https://m.ebay.com/itm/antique-silver-coin-Russian-Empire-ERROR-CURIOUS-UNIQUE-unfinished-coin/272958839295?hash=item3f8d9d59ff:g:W3EAAOSw5cNYF43n
And...this one. What?
https://m.ebay.com/itm/Czechoslovakia-ERROR-coin-German-occupation-Bohemia-and-Moravia-1-Koruna-1942/252758291288?hash=item3ad9917358:g:qAcAAOSw5cNYmMKT
I find the last one weirdly funny.
https://m.ebay.com/itm/1-cent-uncirculated-99-off-centre-mistruck-U-S-A-error-coin-RARE-AS-PENNY/152470592663?hash=item237ff49c97:g:teYAAOSwuxFYxkTG

Here are some coins like you posted first
https://www.m-dv.ru/catalog/id,4658/prohod.html

Citeer: "tolnomur"​Here are some coins like you posted first
​https://www.m-dv.ru/catalog/id,4658/prohod.html

​That is very interesting!
A quite precious coin.