MikeD, are sanctions voted on by the Assembly of the Republic? If so, one would think that PPC and Costá, between them, have quite enough votes to pass sanctions.
Normally yes, sanctions are voted in Parliament, but if any vote on sanctions happens it will only be in early October as Parliament is closed due to the summer recess and then you have the local elections campaign. The government position about Venezuela is quite vague, they don't support them but are very careful in condemning the regime. PSD and PPC are much more blunt in accusing Venezuela. I would dare to say that if PPC was in power right now, Portugal would have the same position Spain has.
If a vote happens, PSD, CDS and PS have more than the necessary votes to approve sanctions, 193 votes out of 230. BE and CDU would, of course, vote against them, but i don't know if PS would take an official position. This is just, theoretical, but PSD/CDS would vote in favour of sanctions, BE/CDU against them and PS could give freedom of vote to their MP's and, easily, sanctions would be approved.