Questions about example sentences with, and the definition and usage of "Yoshi"

A: Yoshi is the name of a Mario character but since she said call her Yoshi it maybe a nickname off of her real name or other real name. hoped I helped and not confused you

A: × I'm yoshi from law department.
✓ I'm yoshi from the legal department.

× I've just transferred to law department one weeks ago, so I send this e-mail for greeting everyone.
✓ I just transferred to the legal department one week ago, so I am sending this e-mail to greet everyone.

× I am so happy can work with you.
✓ I am so happy I can work with you.

× Since I just come newly, I think that I will make many troublesome to you, I apologize in advance.
✓ Since I am a newcomer, I apologize in advance for the troubles I expect I will make for you.

× I will study hard that make myself adjusting workload quickly.
✓ I will study hard to adjust to the workload quickly.

Make sure to check the name of the department- I corrected it to Legal because that is the most common name for that department in the US.