Excel 365 macro enabled file and Sharepoint

[mopey12345]

Hi everyone, advice guidance please. I have inherited a large co-authored appointment spreadsheet (150 + worksheets 10mb) saved in a member of staff's Sharepoint personal folder. Primarily users change background cell colours manually. Is it possible to save the file as an xlsm and with the vba code to do this colour change on selecting the cell, and still co author? If this is not possible can conditional formatting do the same job? Also what is a reasonable limit for the number of worksheets? Thanks in advance.