You must meet the general competency requirement of 61.385 in all cases.
If you need training to achieve that, it must be conducted by an instructor, or an approval holder.
This training could be conducted without part 141 or 142 coverage, as general competency training does not fall under the definitions of 141 (141.015) or 142 (142.015) training.
Interestingly, training conducted as part of a flight review does require 141 or 142 coverage. However, a flight review that does not include training may be conducted without 141 or 142 coverage.