By system
You probably do not need to replace your accounting system.
The most expensive mistake in this whole exercise is a platform migration nobody required. In most cases the system you already run can meet the requirement. Here is what the mandate actually means for each of the common ones.
We do not resell any accounting platform and we do not sell pre-built integrations. Where a provider advertises support for your system, we test whether it fits your configuration rather than accepting the claim.