If this is an Annex II aircraft:
SLMG class rating:
(1) Subject to paragraph (2) and to the conditions of the licence in which it is included, a
SLMG class rating entitles the holder to act as pilot in command of any SLMG.
If its an EASA aircraft:
TMG Class Rating:
All Touring Motor Gliders having an integrally mounted, nonretractable
engine and a non-retractable propeller.
So there is no differences training specified for SLMG/TMG.