Does the estate pay for an executor's personal lawyer, or only a lawyer acting for the estate as a whole?

Generally, the estate pays for legal work that was reasonably needed to properly administer the estate as a whole — advice on the will, handling the probate application, dealing with creditors, preparing for a passing of accounts — regardless of which specific lawyer the trustee happens to retain to do that work. What the estate isn't automatically on the hook for is a lawyer retained purely to defend the trustee personally, particularly where the trustee is facing allegations of their own misconduct or a removal application driven by something they did wrong.

The distinction that matters is whose interest the legal work actually served: work that benefits the estate and its proper administration is generally a legitimate estate expense, while work that's really about protecting the trustee individually, especially if the trustee is ultimately found to have acted improperly, is more likely to fall to the trustee personally rather than the estate.

Because this line isn't always obvious in the moment, especially early in a dispute, a trustee facing a serious allegation should get advice on how their legal costs are likely to be treated before assuming the estate will automatically cover everything their lawyer bills for.