I work for a temporary agency and they pa me and use a w2 at the end of the year. They take out all my taxes etc. Can I establish a consulting firm as a workers comp adjuster and have the temp agency pay me via a 1099 full pay and have ADP payroll service take out my taxes. Therefore I can write off my transportation as a workers compensation consultant.

That course of action is feasible if you do a lot of traveling during the day.

If, however, you drive from home to a single office, work all day, then return home, THAT travel is commuting whether you get paid under Form w-2 or Form 1099-MISC, and commuting costs are NEVER deductible.

Most temp agencies won't go along with that. So even if it was feasible and practical, its unlikely you will get them to agree.

Several years ago the IRS cracked down on temp agencies, not allowing any more consultant/contractors unless they met all the requirements of being one.
Do you know what they are? There are at least 20. I highly doubt that you can meet even the top 5 of them.