Short answer. No. Rule 78, Section 1 disqualifies anyone who is not a resident of the Philippines from serving as executor or administrator, alongside minors and persons the court finds unfit by reason of drunkenness, improvidence, lack of understanding or integrity, or conviction of a crime involving moral turpitude.
What the law says
No person is competent to serve as executor or administrator who: (a) Is a minor; (b) Is not a resident of the Philippines
Rule 78, Section 1 — Who are incompetent to serve as executors or administrators. Read the full provision →
Non-residence is a disqualification, not just a factor
The Rules of Court do not leave residency to a case-by-case judgment call. No person is competent to serve as executor or administrator who: (a) Is a minor; (b) Is not a resident of the Philippines. Residency is listed alongside minority as an automatic bar; someone who does not reside in the Philippines simply is not eligible to be appointed, regardless of how close they were to the decedent or how capable they might otherwise be.
Why residency matters for this role
An executor or administrator has to manage estate property, deal with creditors, appear before the probate court, and eventually account for and distribute the assets. A person based abroad is harder to reach for these ongoing court obligations, which is presumably why the rule treats non-residence the same way it treats being a minor: a fixed disqualification rather than something weighed against other qualities the candidate may have. The concern is practical rather than about the person's honesty or competence, since even a highly capable relative living overseas cannot readily appear whenever the probate court needs them to.
The other disqualifying grounds
Residency is only one of three grounds the rule lists. A person may also be found incompetent to serve if the court considers them unfit to execute the duties of the trust by reason of drunkenness, improvidence, or want of understanding or integrity, or by reason of conviction of an offense involving moral turpitude. Unlike minority and non-residence, this ground calls for the court's own assessment of the individual, rather than applying automatically.
What this means in practice
If the person named executor in a will, or the relative who would otherwise be preferred as administrator, does not reside in the Philippines, the court cannot appoint them to that role no matter how suitable they seem. The estate would instead need a different executor or administrator who meets the residency requirement, and the disqualified person's role in that case is limited to whatever else the law allows, such as nominating or seeking the appointment of someone eligible. This applies regardless of citizenship — a Filipino citizen who has simply moved abroad and no longer resides in the Philippines faces the same bar as a foreign national would.