If you're looking for portability with ergonomics I've been very interested in following Ben Vallack's advice in this video https://invidious.weblibre.org/watch?v=iOupyi-lQZM, which is to take a small keyboard like the gergoplex[0] and strap it to your thighs with a giant rubber band.
I've been looking for a gergoplex but gboards.ca has been down for a long time. If you read the later blog posts on web.archive it's a sad situation, I doubt it'll be back online.
You may also be interested in https://southpawdesign.net/collections/all as they have a few small, ergonomic keyboards.
[0]: https://www.gboards.ca/product/gergoplex-heavy