Yes, Japanese also found difficulty when learning Chinese language at very first time. But their difficulty is very different than difficulty faced by English speakers who learn Chinese at first time.
Japanese usually learn more faster about Chinese characters in Mandarin than English speaker people for example.
Mandarin pronunciation and tones is troublesome for first learners from Japan. Mandarin grammars slightly hard but some adaptation they can learn it.
There are also exist some false friend vocabularies between Chinese-Japanese languages.
So it's mixed but Japanese usually learn more faster.
Example like…
For Mandarin beginners of English speakers, they first need learning how to write correctly those Chinese characters correctly, how to memorize it and how to pronounce it.
But for Mandarin beginners of Japanese, they only just learning how to pronounce it correctly in Mandarin.
Notes: in Japanese is read as Keisatsu and in Mandarin is read as Jingcha, meaning is police.