What do we mean by 'business grammar'?
Well, there are plenty of websites offering it:
Business English - Grammar
Business English Grammar Exercises/Quizzes (ESL/ELL - Prepositions, Articles, Verb Tenses)
Business English Grammar Lessons
With the promise of 'games':
Business English grammar games/ worksheets | TEFLtastic blog
And what do we mean by 'business English', for that matter?
Business English Vocabulary and Grammar Exercises for ESL Students
I wouldn't agree with this:
11 Common Grammatical Mistakes And How To Avoid Them - Business Insider
But this sounds reasonable:
20 Basic Grammar Rules for Business Owners
It is a question of balance:
Jay Doubleyou: fronted adverbials
Gird your fronted adverbials: 14 grammatical mistakes in the schools White Paper | News