Bologna creates a common language
Germany, Austria and Switzerland are part of the European Higher Education Area. The Bologna Process established the bachelor's and master's as a common structure and, with ECTS credits, created a uniform measure of academic achievement. As a result, degrees are broadly comparable across national borders, which considerably eases recognition.
The Lisbon Recognition Convention and the burden of proof
The Lisbon Recognition Convention of 1997 has been ratified by Germany, Austria and Switzerland. Its core is strong: a degree obtained abroad is recognised unless the assessing body demonstrates a substantial difference. The burden of proof therefore lies with the body that wishes to refuse, not with you. This is an often overlooked but powerful principle.
In practice, the assessment runs through the national ENIC-NARIC centres, which specialise in cross-border recognition.
Where it gets more complicated: regulated professions
For regulated professions, for example in medicine, nursing, law or teaching, the academic degree alone is not enough. Here, additional bodies assess professional licensing under their own rules. A distance-learning degree can be academically sound and still require further steps to practise the profession in a neighbouring country. This is not a shortcoming of distance learning; it applies to any foreign degree.
What you can do in practical terms
Clarify three points early. First: is your target profession regulated? If so, seek information from the relevant professional body in the target country. Second: is the institution state-recognised and the degree programme accredited? That is the basis of any recognition. Third: ask the ENIC-NARIC centre of the target country for an assessment before you commit.