UBA Spanish for Extranjeros courses have been highly recommended on this Forum by several students
From what I know, the courses they offer at the moment are all via zoom, but the group sizes are smaller due to there being less foreigners here at the moment - which can be very beneficial for individual learners in a group context.
UBA courses don't place that much focus on conversation, BUT they provide a solid, and importantly well structured, gramatical base that
compliments day to day exposure to the language making progress quite fast (e.g. within 2 years people go from 0 to spontaneous and conversational) They also provide good context of Argentine specific culture and ways of speaking.
Good value for money too apparently.
Perhaps an UBA course plus a personal conversation coach + regular local language content consumption would be the fastest way to progress if time permits? At least until ones confidence in speaking is built up.