Flexicontent v5 use joomla templating system you can use plain text or html to generate your email notification
1 go to email templating
2 filter flexicontent in component
3 you can edit each email notification
{if variable} true
{if !variable} false
{if variable empty} Strictement empty
{if !variable empty} not empty
{if x=valeur} 1 value true
{if x!=valeur} not value equal
{if x in a,b,c} 1 value in list
{if x not in a,b,c} no value in list
{if x contains texte} 1 value in text
{if x not contains texte} no value in text
{if x>n} >= < <= numerique comparaison
exemple
{if catid=11}
content for categorie 11
{/if}
{if incat in 18,19}
content for multicategorie item
{/if}
{if !field_description}
content if description is not empty
{else}
Description : {FIELD_DESCRIPTION}
{/if}
{if field_price>=250000 and field_floors=3}
content if field price have value between 250000 and 3
{elseif field_price>=100000}
or after 100000
{/if}
{if field_tags contains "maison"}
Maison
{/if}
&& || ! are supported