The word must be international because we use the word "cosplay" as well. Some people may not know the word so explaining the them, "They like to dress up as a character from a book, film, or television show." would help clarify what a cosplayer does.
私達も"cosplay"という言葉を使うので、cosplayerと言う語は世界で使われているに違いありません。その語を知らない人がいるかもしれないので、説明をした方が良いでしょう。
"They like to dress up as a character from a book, film, or television show." （彼らは、本、映画、ＴＶ番組のキャラクターのような恰好をするのが好きだ）と言えばcosplayerがどういう人かはっきりと説明するのに役に立つでしょう。
The act of playing with costumes is called "cosplay"and the person who likes to do it would be called a "cosplayer".
For example, you might say something like:
-I enjoy cosplay because it's satisfying. Everyone at work knows that I am a cosplayer.
コスチュームを着るて行動する事を"cosplay"（コスプレ）といいその様な事をする人の事を"cosplayer"（コスプレイヤー）と呼びます。
例えば、次のように言うかもしれません。
【例】
-I enjoy cosplay because it's satisfying.
（満足することが出来るのでコスプレを楽しんでいます）
-Everyone at work knows that I am a cosplayer.
（職場のみんなは私がコスプレイヤーと言う事は知っています）
"Cosplay" is a hobby where people dress up in outfits as characters from movies or comics.
For cosplay, I will be dressing up as Batman.
A person who partakes in cosplay is called: "A Cosplayer"
If there are more one then they are called "Cosplayers."
eg: I am a cosplayer.
"Fancy Dress" is another word for cosplay where people dress up as characters
eg: There is a fancy dress party this weekend.
"Cosplay" （コスプレ）とは趣味で映画や漫画のキャラクターの衣装を着ることです。
For cosplay, I will be dressing up as Batman.（私はバッドマンのコスプレをします。）
コスプレに参加する人を"A Cosplayer"（コスプレイヤー）と言います。複数人の場合は"Cosplayers"と言われます。
例文：I am a cosplayer.（私はコスプレイヤーです）
"Fancy Dress" （素敵な服）はコスプレを表す別のフレーズです。
例文：There is a fancy dress party this weekend.（今週末コスプレパーティがあります。）
That teenager likes going to Star Trek conventions
In the UK there are cosplay groups, but generally, 'cosplay' is not a familiar word and people are very hazy about what such costumed individuals get up to when they meet. Better known would be costumed reenactment groups, probably just known as 'reenactment groups' who get together to reenact perhaps , an historical battle in uniform. Other groups may dress in the clothing of some famous comic, TV or film characters and meet at a convention to exchange ideas and gather impressions
英国にもコスプレグループ（cosplay group）はありますが、「cosplay」という言葉はそれほど一般的ではありません。そういう人たち（コスプレイヤー）が集まって何をするのか、分からない人が多いです。
英国では、制服を着て歴史上の戦いを再現する「reenactment group (costumed reenactment group)」の方がよく知られています。
ほかに、有名な漫画（comic）、TV、映画の登場人物の衣装を身に着け、集会で意見・感想を言い合ったりするグループもあります。
examples
Cosplay is a term meaning Costume Play, usually linked to a comic book or manga culture.
Comic fans dress as their favourite characters and attend functions and events in that costume.
Fancy Dress can encompass a broader range of costumes including historical, movie characters etc..
Cosplay is an abbreviation for 'costume playing' so a person that like to do this is called a 'cosplayer' which is short for 'costume player'
cosplayers wear costumes to make them look like a character
カナダ 
南アフリカ 
イギリス 
