Hi all,
this post is sort of a “follow-up” of https://discourse.ubuntubudgie.org/t/nemo-settings-and-nemo-terminal-19-10-20-04/2727, at least for what concerns nemo-terminal, and iI’m writing hoping to help someone.
As I’ve told in above quoted post, Ive found pretty impossible to install and use nemo-terminal on Budgie 20.04; I’ve made things even worst by adding Mint Ulyana in sources.list (I’m very grateful to those girls and guys who created VMs and mostly VMs snapshot!), since this makes your distro an hybrid at first upgrade, getting Mint in response to a lsb_release -a when she was born Budgie (she, because my machines are girls: having at home an husband and a 18 yo son - even if offset by a female Jack Russel Terrier - please, let me call “girls” my machines 
).
So I’ve tried to install nemo-terminal via dpkg after having got deb from Ulyana repositories but I’ve found a bunch of problems from dependencies and an apt - f install simply removed nemo terminal.
Finally I’ve found sort of a workaround getting from Ulyana repos every deb needed for installing nemo-terminal (w/o adding Ulyana to sources.list) and “dpkg-ing” them: everything worked at its best (just for upgrading packages I need to check versions on Ulyana repos by hand, but it isn’t such a big problem: benefits from having nemo-terminal installed and working are greater than need of checking packages versions once a week, moreover that I’ve also disabled automatic updates since I prefer doing it by hand, once a week or once I get a CVE warning).
Involved packages are : gir1.2-nemo-3.0, gir1.2-xapp-1.0, nemo-terminal_4.6.0, python3-xapp_2.0.1, python-nemo_4.6.0, from Ulyana repos.
Silvia