People about Cosplay...
When judging whether something is cultural appropriation, ask first: is there a cultural double standard that praises the borrower while punishing those whose behaviors/styles are being borrowed from? If not, then the second test is to see if the thing being borrowed has religious/spiritual/historical significance the borrowers are disregarding or disrespecting for the sake of ‘cool’. Finally, does the act of borrowing reinforce stereotypes?
To answer your question, No. Cosplaying in the past hasn’t been used to marginalize, dehumanize, or stereotype the Japanese people. Cosplay has no major religious, political, or spiritual significance, even in Japan it is considered a commercial hobby. Cultural Appropriation is problematic because the hegemonic group (in the US case, white people) get praise for behaviors the group that they borrowed the practice from get penalized for (in this case, Japanese otaku). However, Japanese otaku have the same or superior status as American Cosplayers at US Conventions and English language internet. Japanese Otaku are not facing a double standard when compared to white otaku that favors White otaku.
There are some racists who may say white cosplayers look more like the anime/video game characters then Japanese cosplayer, but those types tend to be seen as racists and pariahs in most well-balanced cosplay communities. Most people tend to think the Japanese have very high quality cosplay.
For me, cosplay is the art of bringing a fictional character to life using yourself as a medium. As people have already mentioned, cosplayers put a lot of money, time, and energy into their craft. Some will go to extremes to lose weight or learn a technique outside their skill level just to try and cosplay that character.
I really love cosplay and I find it is a mirror of how you will treat a lot of things in life, whether that is your job, your relationships, etc. The typical time and project management questions always appear (“Can I finish this in time for this convention?”, “Do I have the resources?”, etc.) but also some that you may not expect (“Should I just stitch this poorly to save time?”, “Will cutting a corner here affect the project later on?”, “Should I invest the time in learning this new technique and apply it to the costume?”). The way you answer these questions are exactly the same way you will answer these questions in real life.
That’s why cosplay is such a great way to make friends than other activities. Not only do you have a great excuse to geek out to like-minded people about your passions, you also can see whether or not they do as they say. You really get to know the people and can truly bond with them.
Coming from a movie production background, you put on the parts of your costume that would interfere with makeup – possibly rubbing on your face when donning the apparel – before you put on makeup. None of the rest of your costume should be worn until it is just before “showtime”.
And costumers (both hobbyists and professionals) should be planning for makeup application and making a costume that can be put on without having to go over the head like a T-shirt does. Aside from the fact that this is easy to make, there really isn’t a good excuse for designing a costume that ruins makeup, or alternately, has to be worn while makeup is being applied.