That looks like an angled stress crack. If you can clean it out, an elastomeric sealant will absorb the compressive stresses much better than the 'solid' masonry filler. The better elastomeric sealants, ('MS'), are also overpaintable.
@mespilus started
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That looks like an angled stress crack.
If you can clean it out, an elastomeric sealant will absorb the compressive stresses much better than the 'solid' masonry filler. The better elastomeric sealants, ('MS'), are also overpaintable.