The words "solution" and "architect" both have enterprise and old-economy connotations; you will probably not see them too often in startup world. Small and early stage startups don't really separate architecture from implementation in terms of personnel and responsibilities. Later in life the people with more architecture and less implementation responsibility could be Staff Engineers, Sr. Staff Engineers, Principal Engineers, etc.
I’ve mostly seen Solution Architect treated synonymously with Sales Engineer or Forward Deployed Engineer.
Solution architects are ways to extract money from dinosaurs, not useful at a startup.
I've seen architecture roles in startups that focus on legacy industries, like public sector or banking. Consider adjacent roles like engineering manager or technical program manager if you have delivery experience. Another opportunity is a senior position in a startup's professional services arm, similar to forward deployed engineer but may have titles like implementation engineer, customer success engineer eer, or solution architect.
Try: https://topstartups.io/jobs/?role=solution+architect
https://angel.co/jobs should pull up some too
startups need people that do things rather than talk about it
Rather than speculating how titles translate across work cultures, can you elaborate on what your own responsibilities and strengths have been as a Solution Architect in these recent roles?
That should enable people here to share what titles have fulfilled those responsibilities in their orgs.
Edited to add: I will mention that many early/small startups expect their CTO to take responsibility for most significant technical direction and architecture, and lesser but still non-trivial architectural responsibility gets handed down to daily grind developers. It can take some growth before there's room for an intermediate role that focuses specifically on architecture.