Did Lady Gaga inspired Beyonce to be a visual artist?
When Lady Gaga started the trend of visual/artistic music videos, Beyonce followed the trend on the release of 4 ("Run The World" music video) which is unusual for Beyonce. Beyonce wasn't even a visual artist in the past not until Lady Gaga came to the scene.
Beyoncé put out a video anthology album for B'Day in 2007. 4/BEYONCE/Lemonade was always something she wanted to do since then and she only managed to improve with each era.
Gaga influenced other artists for the reasons you gave, but Beyonce was already doing it. She had an aesthetic already in mind for both B'Day and IASF music videos.
How wasn't B even a visual artist? Didn't she make any music videos? Do you know B'day Anthology? Yep, she was low budget for teh most part but she surely did good work way before Gaga. Gaga only bought up eccentricity to teh table.