>>39046714chan has buttons for searching images on Google, Yandex and SauceNAO, and there are multiple add-ons to have reverse search images everywhere.
From personal experience:
- Google is the best for recently created media and stuff from Twitter (since it crawls the site every hour)
- SauceNAO is the best for images that would belong in a booru or hentai site and for uncropped/non-edited screenshots of anime
- Yandex is the best for cropped images and real photos, and for finding other resolutions of the same image
- Google and Yandex have "safe search" enabled by default and it cripples the quality of your results
- At first it looks like you need an account to change Yandex's search settings, but you can access them on
https://yandex.com/tune without an account
- Google has two search modes: the new "Google Lens" that only suggests similar images and takes an additional click to see sites containing the image you are searching, and the old search that can be used with
https://www.google.com/searchbyimage?sbisrc=cr_1_5_2&image_url= the_url_of_the_image_you_are_searching.format_of_the_image (there are add-ons to simplify this)
- creating an account on SauceNAO increases your daily search limit to 100 searches per day
- 4chanX, an advanced userscript for 4chan with hundreds of settings, allows you to customize the list of image searchers and even go to the source for files with specific filenames (like Pixiv's 1xxxxxxxx_p0)
