Embedding video using Craft 3 'Video Embedder' plugin
Worked it out - just needed to use the right syntax, for example:

{% set embed = craft.videoEmbedder.getEmbedUrl(entry.videoEmbed) %}

{% if embed | length %}
&lt;div class="embed-responsive embed-responsive--mb-l embed-responsive-16by9"&gt;&lt;iframe src="{{ embed }}" width="100%" height="600" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen&gt;&lt;/iframe&gt;&lt;/div&gt;
{% endif %}